There are 271 Hydroculus in total found in Fontaine for Genshin Impact. They are collectible items used to level up the Statue of the Seven. See all Hydroculus locations with our interactive map and how to get them here!

Elemental Oculus Items
Anemoculus	Geoculus	Electroculus
Dendroculus	Hydroculus	Pyroculus

Interactive Hydroculus Map

Hydroculus Locations Map

Note: You can toggle the Area drop down menu to see other Fontaine map areas!

The Nostoi Region and Sea of Bygone Eras, have a total of 55 Hydroculi, bringing the overall total Hydroculus to 271!

Fontaine Map Guide

Surface Hydroculus Locations

All Hydroculus Locations in Fontaine's Surface

Select a surface section below!
4.0 Locations Beryl Region Belleau Region Court of Fontaine	4.1 Locations Liffey Region Fontaine Research Institute
4.2 Locations Erinnyes Forest Morte Region	4.6 Locations Nostoi Region
Tip: Use your browser's page search function to navigate the page by searching a Hydroculus number from the map!

4.0 Surface Hydroculi Locations

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No.	Image	How to Get
1		Located on top of the boat near the docks. Use the Waverider Waypoint at the beach beyond the nearest waypoint to get there and use the Four-Leaf Sigil located at the bottom of the Hydroculus.
2		Located just ahead of the Romaritime Harbor Statue of Seven. Climb up near the pillars then just glide down to get the Hydroculus.
3		Located on top of the mountain by the Denouement of Sin artifact domain.
4		Located on a hill, the Hydroculus is on top of an artist easel with a blank canvas, facing the direction of the West Slope of Mont Automnequi.
5		Located on the side of the mountain, inside a hole dug into the ground surrounded by Meka enemies.
6		Located on top of an incredibly tall rock, north of the nearest surface teleport waypoint. There is a nearby tower with two Clockwork Meka enemies at the base of the rock.
7		Find 3 Seelies to summon a hydro ring. Ride it to the top of a platform that gives you a jumping boost and jump to the Hydroculus and a chest!
8		Located floating high above an arena east of the Beryl Region. Follow the Seelie nearby to its Seelie Court to activate hydro rings. Then, go at the top of a nearby cliff then use the hydro ring there to propel yourself towards the Hydroculus.
9		Located at the peak of a rocky mountain near the center of the Beryl Region.
10		Located at some ruins west of the Statue of the Seven in the Beryl region.
11		Located floating beside a floating ship. Defeat the Hydro Hilichurl Rogue in this area to gain access to this ship. Then, use the Pneuma Block to unlock both a Remarkable Chest and a path to the Hydroculus.
12		Located on top of a rib-like stone at the center of the Elynas, Beryl region
13		Located on top of a rib-like stone pillar north of the Elynas waypoint.
14		Located north of the Elynas area, at the tip of another rib-like stone right beside a Hilichurl camp on the beach.
15		Located at the tip of a rib in the upper-center Elynas area of the Beryl Region. Glide down to this area from the nearby cliff-top teleport waypoint or climb the rocky outcrop to the Hydroculus.
16		Located on top of a small mountain east of the Statue of Seven in the Beryl Region.
17		Located on another boat southeast of the Statue of Seven in the Beryl Region.
18		Located on another boat south of the West Slopes of Mont Automnequi. Climb up the boat and jump to get the Hydroculus.
19		Located on an island south of the West Slopes of Mont Automnequi. The Hydroculus is guarded by an Anemo Hilichurl Rogue.
20		Located on top of a small rocky mountain north of the Emperor of Fire and Iron location. Climb up this mountain to get this Hydroculus.
21		Located floating in the air by the Aquabus path in West Slopes of Mont Automnequi. Use the Hydro Rings on top of the house to grab the Hydroculus.
22		You can either climb the rocky mountainside and use anemo on the pinwheel at the top to get to the Hydroculus, or you can find Antoine at the base of the mountain and use pneumosia to ride his flying balloon ship all the way to the Hydroculus.
23		Located inside the Aquabus tunnel in the West Slopes of Mont Automnequi.
24		Located at the tip of a spiral shipwreck structure in Poisson. Climb up to reach this Hydroculus.
25		Located on top of a tower guarded by Meka dogs. Find the nearby pneuma and ousia blocks to solve the puzzle, defeat all meka dogs to unlock the remarkable chest and use the resulting hydro ring to get to the top of the tower.
26		Located on top of a house right by the water, north of the West Slopes of Mont Automnequi.
27		Located in the middle of the three islands south of the Court of Fontaine, just above the water. Take a Waverider and exit just below the Hydroculus to be able to reach it.
28		Located on an island north of the Belleau Region, guarded by a Clockwork Meka.
29		Located floating above the water southeast of the Court of Fontaine. Find 3 Seelies underwater to activate the Echoing Conch. After activating, the fish will gather. Enter the hydro ring located within the group of fish to launch yourself upwards towards the Hydroculus.
30		Located on the roof of the train station entering Court of Fontaine. Get here by climbing or using the hydro ring at the base of the structure.
31		Located east of the Opera Epiclese, floating high above the water. To get it, jump on the boat in the area and successfully fish one time to summon a hydro ring. Then, climb up the highest part of the boat, glide towards the hydro ring and enter to launch yourself upwards.
32		Located under the bridge entering the Court of Fontaine by way of Aquabus.
33		Located on a small structure above the water, south of the Court of Fontaine. Use the hydro ring to grab the Hydroculus.
34		Located on top of the large green arch at the center of the Court of Fontaine. Climb the arch from the sides to get to the Hydroculus.
35		Located submerged in the shallow pond northeast of the Court of Fontaine, still within the city walls.
36		Located on the roof of a circular building north of the Court of Fontaine, attached to the outer wall.
37		Located on the top of the largest building in the Court of Fontaine.
38		Located northwest of the Court of Fontaine by the shoreline. Solve the Seelie puzzle to summon an updraft that can carry you towards the Hydroculus. Seelie Locations: ▸1st: Dig up in the sandy area ▸2nd: Behind the boulders northeast of the area ▸3rd: Floating high above the area; get a high vantage point then glide down to the Seelie
39		Located on top of a tower northwest of the Court of Fontaine. Defeat the Meka surrounding the tower to unlock the chest and summon a hydro ring you can use grab the Hydroculus.
40		Located on top of a silo in a settlement northwest of the Court of Fontaine.
41		Located on a lavender field northwest of the Court of Fontaine, near a teleport waypoint. Use the clover pinwheel in the field to launch yourself up to the floating Hydroculus.
42		Located at the top of a Hilichurl Base northwest of the Court of Fontaine.
43		Located at the end of the water canal north of the Court of Fontaine.
44		Located northeast of the Court of Fontaine. Dive underneath the Antoine Aircraft and borrow the nearby Aberrant Stingray's power to cut off the Yellow Fontemer Seagrass sticking to the craft. Simply ride the aircraft up using the pneumosia device until you reach the Hydroculus.
45		Located at the top of the mountains north of the Court of Fontaine.
46		Located on top of a tree at Marcotte Station, just south of the teleport waypoint. you can use the hydro ring to grab the Hydroculus on the way to the top of the cliff.
47		Located at the center of the fountain at Marcotte Station, on the way south of the Fountain of Lucine.
48		Located under the center of the bridge at the Opera Epiclese.
49		Located at the very top of the tall archway at the end of the Opera Epiclese overlooking the water. Climb the archway to get the Hydroculus.

4.1 Surface Hydroculi Locations

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No.	Image	How to Get
86		Located south of the Liffey Region Statue of Seven. Climb the nearest high platform and glide towards the Hydroculus.
87		Located just southwest of the Liffey Region Statue of the Seven high up the mountaintop. Simply climb the mountain to obtain it.
88		Located near the Statue of the Seven in the Liffey Region. Look southeast to see the Hydroculus on a tiny pillar.
89		Can be found floating above the river in Mont Esus East, near the Large Pneumousia Relay Station.
90		Located on a buoy floating south of Mount Esus East.
91		Located by the cliff north of Mont Esus East. Collect hydrogana and activate the hydro mechanism to make a temporary bridge to the Hydroculus.
92		Can be found north of Mont Esus East, near the Large Dendro Slime.
93		Continue north from #92 to find the Hydroculus floating above the box crates.
94		Located far north of Mont Esus East, on top of the tower. Use the Hydro ring on the cliff to quickly reach the tower's peak.
95		Located in the northernmost tip of the Liffey region, on the highest point of a small island inhabited by Hilichurls.
96		Located north of the Millennial Pearl Seahorse, on top of the tallest pipe.
97		Climb to the top of the tall golden tower north of the New Fontaine Research Institute to find the Hydroculus.
98		Located on the map's northernmost edge, north of the New Fontaine Research Institute, and is guarded by a Frost Operative. You can utilize Venti's or Kazuha's skill to reach the Hydroculus, or a geo construct like Geo Traveler's or Zhongli's.
99		Situated on the highest cliff to the north of the New Fontaine Research Institute. You can climb the cliff from the northern teleport waypoint and obtain a Luxurious Chest in the same location!
100		Located on the rocky mountain to the northwest of the New Fontaine Research Institute. Climb up from the teleport waypoint to get there.
101		Located at the center of the New Fontaine Research Institute area, on top of the tent roof.
102		Located in the gap of the broken bridge leading out of the New Fontaine Research Institute.
103		Break the Hydro Stone to summon a Hydro Ring, then ride it to the puzzle above, where you can reach the Hydroculus and obtain an Exquisite Chest if you shoot all the targets.
104		Located east of the Fontaine Research Institute by a stairway.
105		Located beneath the ruins northeast of the New Fontaine Research Institute.
106		Located at the very top of a tall tower to the north of the Central Laboratory Ruins.
107		Located inside a locked ruin, northwest of Central Laboratory Ruins. Unlock the door by recharging the Terminal with a portable storage energy.
108		Located slightly north of the Central Laboratory Ruins Teleport Waypoint, at the end of a ruined bridge. Simply glide down from the Waypoint to the end of the bridge.
109		Located in a ruin in the Central Laboratory Ruins. Dive into the water and swim to it.
110		Head to the center of the Central Laboratory Ruins, then climb the floating debris until you reach the uppermost piece, which contains the Hydroculus.
111		Located at the end of a broken bridge, southeast of Central Laboratory Ruins.
112		Can be found inside a hilichurl camp, south of the Teleport Waypoint, in the claw of a metal sculpture.
113		Located immediately north of the Fontaine Research Institute Statue of the Seven at the end of a broken bridge. Glide from the Statue of the Seven and traverse the broken bridge until you reach the end where the Hydroculus is located.
114		Located at the base of the broken bridge south of the ruins of the central laboratory.
115		Located just southwest of the Fontaine Research Institute, in between of a damaged pillar.
116		Located west of the Fontaine Research Institute Statue of the Seven, at the very end of a broken bridge.
117		Found on top of a tall pillar to the west of the Fontaine Research Institute Statue of the Seven. Glide over from the nearby Teleport Waypoint to obtain it.
118		Located on a short bridge pillar southwest of the Fontaine Research Institute teleport waypoint. To get it, simply swim and climb the pillar.
119		Located in the Fontaine Research Institute Region, behind a fallen pillar and west of a Teleport Waypoint.
120		Located on a tiny mountain across the broken bridge from the Liffey Region Statue of the Seven. Simply climb the mountain to obtain it.
121		Located on a mountaintop southwest of the Fontaine Research Institute Statue of the Seven. To get it, use the Teleport Waypoint nearby, then proceed southwest and climb the mountain.
122		Located on top of the broken wall around the arena of the Experimental Field Generator.
123		Located on top of a small tower to the south of the Experimental Field Generator. Simply glide off the nearby cliff to get it.
124		Located near the southern Teleport Waypoint in the Fontaine Research Institute, within a bubble with a Luxurious Chest. Remove the bubble barrier by locating and following the two Seelies nearby. Seelie Locations: ▸1st: Activate the Hydro mechanism by hitting it with Hydro Attacks. ▸2nd: Destroy the Jadewater Fruit using Elemental Attacks to reveal the Seelie.
125		Located on a building's roof southwest of the Fontaine Research Institute Statue of the Seven. Simply glide from the bridge's top to obtain it.
126		Located southeast of the Fontaine Research Institute Statue of the Seven on top of a ruin. Simply climb the ruin to obtain it.
127		Located in a small ruin upstream, east of the Fontaine Research Institute Statue of Seven.
128		Located on top of a small house in the southeast part of the Fontaine Research Institute area.

4.2 Surface Hydroculi Locations

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No.	Image	How to Get
151		Situated on top of a dead tree north of Marcotte station.
152		Can be found to the north of Marcotte station. Can be reached by gliding from the tiny mountain to the south of it.
153		The oculi can be found to the north of Loch Urania. Investigate a fast moving object on the water to solve the puzzle. It's a seelie, which will lower the water level and reveal an exquisite chest.
154		Located on the summit of a small mountain north of Marcotte Station, next to a Time Trial Challenge.
155		Can be found southwest of Loch Urania. Grab the octopus power again to push the jellyfish, using it to reach the oculi.
156		Can be found on top of Loch Urania's huge bubble.
157		The oculi is located to the east of Loch Urania. Finish the three anemo monuments puzzle, and an Eye of the Storm will appear. If its HP falls below a certain threshold, it will flee, causing a wind current. Fly up and collect the hydroculus, and the eye of the storm may be fought again.
159		Can be found north of Weeping Willow Lake, inside a tent next to a foe named Rocky.
160		Situated on top of some ruins to the right of the Lake's Weeping Willow.
161		Located east of the Weeping Willow of the Lake. Clear out the Bacteria Mats on the small pond. Then dive and follow the revealed path. The Hydroculus will be at the end, under a sewer grate.
163		Placed on top of a small hill in the northeast part of Erinnyes.
164		Placed on top of a big rock east of Weeping Willow Lake, and treasure hunters can be found at the base of the rock.
165		Located southeast of the Weeping Willow of the Lake, submerged in a small lake. Use the Xenochromatic Ball Octopus located east of this lake so you can dive underwater and get the Hydroculus.
166		Located southeast of Weeping Willow Lake; release the three jellyfish to receive the oculi. Jellyfish 1: Put out the flame from the torch. Jellyfish 2: Light up 4 Hydro Monuments in order according to the number of pinecones surrounding each one. Jellyfish 3: Defeat the Pyro slimes.
167		Can be found in Weeping Willow of the Lake, between the tree roots.
169		On top of rock cliff next to an Anemo Hilichurl Rogue.
170		Contained inside a huge shell near the Statue of the Seven by Marcotte Station. To open the shell, hit it.
171		The oculi lies near the Statue of Seven by Marcotte Station. You can use the Humongous Hat Jellyfish near to bounce to it, then glide or climb the tree.
173		Can be found south of the Weeping Willow of the Lake waypoint, on a rock overlooking the massive tree.
174		Ride the aircraft near the Fountain of Lucine at the mountain's foot. After reaching the top of the mountain, utilize the hat jellyfish that has spawned to reach the oculi.
176		Located south of the Weeping Willow of the Lake. Complete the Time Challenge to reveal and access the Hydroculus.
177		The oculi are locked up behind bars. Simple vault keys 1, 2, and 3 are required to open. Key 1: Get from the bird's nest on top of the shipwreck. Key 2: Defeat the Treasure Hoarders to open up the chest on the deck. Key 3: Dig the spot on the south side of the shipwreck.
178		Situated on top of a cliff north of Lumidouce Harbor.
181		Can be found near the fork east of the Foggy Forest Path. Take the octopus ability from the machine and use it to get rid of the bacterial mats (three total). The hydroculus will then spawn, and both jellyfish will be freed and moved into position. Make use of them to get the hydroculus.
182		Follow the foggy forest trail south of the waypoint from the fountain. The oculi is located beneath the bridge with a treasure hoarder and may be acquired simply by going across the bridge.
183		Placed inside the Pneumousia Storage Box; break it using the ousia orb nearby.
184		The oculi can be found near the waypoint south of the Fountain of Lucine's southeast exit. Use the machine to obtain the ball octopus ability, then use its powers to push the hat jellyfish. Use the jellyfish to jump and then glide to the oculi.
185		Near the waverider waypoint on the foggy forest path. Use the machine to gain the ability of xeno octopus, then push the jellyfish to jump and glide.
186		Located southeast of the "Rusty Rudder" boat. Swim underwater and use the jellyfish to jump up.
187		The oculi is located in Lumidouce Harbor. Obtain the octopus ability, hit the floating crystal flowers to make them spin, then use the platforms generated to approach the jellyfish.
188		Placed on the left crane near the Lumidouce Harbor waypoint.
190		Located north of the Fort Charybdis Ruin. Take the two floating crystal and set them on the projector. Align the projector with the mirrors using the octopus ability.
193		Located in Fort Charybdis Ruins. Complete the Time Challenge located in the area to summon a hydro ring. This will take you to the Hydroculus above.
195		Located by the Morte Region Statue of the Seven, floating above the hole that leads to the ruins.
199		Located northeast of the waypoint, north of Mount Automnequi's West Slopes. Simply utilize the jellyfish beneath it to obtain the oculi.
200		Located near the waypoint, north of Mount Automnequi's West Slopes.
204		Situated on top of a rock wall near the East Slopes of Mount Automnequi waypoint.
207		Can be found on the huge tower in Morte Region. Enter the ring of water near the waypoint, which will take you almost to the top of the tower.
210		Can be found south of the Fort Charybdis Ruin. To obtain the oculi, use the Jellyfish situated on top of the shattered building.
215		Sits on a tiny mountain near a shipwreck southeast of Charybdis Waypoint.
216		Located southeast of 215, near the map's boundary. Eliminate the hilichurls that are blocking the jellyfish, and then utilize it to fly up.

4.6 Surface Hydroculi Locations

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Three of the surface Hydroculus in 4.6 are found around the Village of Petrichor, while the remaining six are found inside the Faded Castle. To gain access to the castle, travelers must play through the Canticles of Harmony quest.

No.	Image	How to Get
217		Can be found on top of a house near the Teleport Waypoint in Petrichor. Simply climb the house and get it.
218		Placed on top of the mountain in the village of Petrichor.
219		Teleport to Petrichor's central Waypoint and head east. The Hydroculus can be found on a pillar behind a tree.
220		Found behind the bookshelf in the faded castle. To open the bookshelf, solve the Mysterious Grimoires puzzle by returning the Lost Grimoire.
221		Located underwater and between two statues near the teleport waypoint. You can simply dive to retrieve it.
222		Located on the left side of the stage of the Faded Castle. Near some musical instruments.
223		Can be found on the Middle Level of the Faded Castle, near the library and past a Praetorian Golem. Hit the crystal and use the moving platform and hydro ring to reach the top. Use the Lost Grimoire to activate the bookcase, then open it using the Ancient Symphony.
224		Found on a ledge in the southern portion of the Faded Castle, on the route to the Exhibition Hall, where the Statue of Marble and Brass is placed.
225		Located at the far end of the arena in the Exhibition Hall of Faded Castle. Climb one of the nearby pillars and jump from there to grab the Hydroculus.

Underwater Hydroculus Locations

All Fontaine Underwater Locations Map

Select an underwater section below!
4.0 Locations Beryl Region Belleau Region Court of Fontaine	4.1 Locations Liffey Region Fontaine Research Institute
4.2 Locations Erinnyes Forest Morte Region	4.6 Locations Sea of Bygone Eras
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4.0 Hydroculus in Fontaine's Underwater Area

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Hydroculus #50 at the Emperor of Fire and Iron Boss

A Hydroculus is located inside the cave pathway leading down to the Emperor of Fire and Iron boss. You can find the entrance by toggling the layer map, and locating the orange mouth of a cave a little north to the boss icon.

Hydroculus #51 to #53 in the Boiling Water Puzzle

	How to Get
51	Can be found under a rock pile, in the room on the way to the Iron Viscount
52	On your way back to the surface, just as you pass the Iron Viscount. The Hydroculus is hidden amongst seaweed on the ceiling.
53	Located in the boiling water. To unlock this area, you will need to solve the Boiling Water Puzzle in the Beryl Region, Fontaine.

Three more Hydroculi can be found on the way to and from the cave of the Iron Viscount mini-boss! To unlock this area, you will need to solve the Boiling Water puzzle in the Beryl Region, Fontaine.

How to Clear Out the Boiling Waters

Underwater Hydroculus #54 to #65

No.	Image	How to Get
54		From the underwater teleport waypoint in Elton Trench, head straight down until you come across signs of shipwrecks, and follow it all the way to a cave. The Hydroculus will be on top of a shipwreck, surrounded by Treasure Hoarders.
55		Located just between two cliffs near the Teleport Waypoint south of Elton Trench.
56		Dive into the depths of the Elton Trench, down past shipwrecks and into the mouth of a cave where the Hydroculus is. This is on the way to Hydroculus #54.
57		Located in an underwater room near the Elton Trench. Use the nearby pneuma block and attack the ousia posts to unlock. See full guide in this page!
58		On top of a giant, underwater lilypad with two Fontemer Aberrants circling it, on the northern side of the Elton Trench.
59		Around north of the Elton Trench, behind a bounder you can destroy with a Crab Aberrant's ability.
60		Located close to the surface north of the Elton Trench, right beside a pair of Bullet Barnacles. Borrow a crab aberrant's ability and use its shield to avoid getting damage from the barnacles!
61		Found underwater in the cave leading to and from the south side of the underground Poisson village, in the Belleau region.
62		Found on top of the giant ship on the north side of the underground Poisson village, in the Belleau region.
63		The Hydroculus was guarded by the Fairy Knight twins, north of Salacia Plain.
64		Can be found under the rock arch, in between the Elton Trench and Salacia Plain.
65		In the small building inside you can find the Hydroculus, south of the Court of Fontaine in Salacia Plain.

Hydroculus #66, #67, #68, and #70 found in the Aqueous Tidemarks Quest

	How to Get
66	In the second area you access during the quest, destroy the Bullet Barnacles to reveal the Hydroculus.
67	Found through a doorway past the second area, at the bottom of some stairs in a circular room.
68	Inside the library of the ruins, on top of a staircase.
70	Inside a small room deep in the ruins, guarded by a pair of Rifthound Whelps.

Four Hydroculi are located in an underwater area locked behind an Ancient Key, which can only be obtained through the ''Aqueous Tidemarks'' world quest!

Aqueous Tidemarks Quest Guide

Hydroculus #69 in a Cave in Salacia Plain

Follow the path south of Salacia Plain into a cave and ride the current inside till you come across the Hydroculus under a small arc. There will be rows of Bullet Barnacles along the way so watch out!

Hydroculus #71 Inside a Locked Underwater Room

How to Unlock the Room in Salacia Plain
1	Take a Crab Abberant's ability
2	Use the ability on the two nearby Fantastic Floating Ball and Rings.
3	Finally, interact with the two machines in front of the room to unlock it.

There is a Hydroculus inside a locked, underwater room in the Salacia Plain. Aside from the Hydroculus, this room will also contain a Treasure Chest!

Locked Underwater Dome Puzzle Guide

Underwater Hydroculus #72 to #76

No.	Image	How to Get
72		Located under a rock arch north of Salacia Plain.
73		Located at the center of a big underwater plant north of Salacia Plain.
74		Located near the bottom of the ocean floor, under an archway of an underwater ruin to the right of the Court of Fontaine.
75		Find 3 Seelies to unlock the big bubble in the Thalatta Submarine Canyon, just by the teleport waypoint
76		Located north of the Chemin de L'Espoir, behind a broken wall at the top of a ruin entrance.

Hydroculus #77, #78, and #79 found in the Narzissenkreuz Adventure Quest

No.	Image
77	Pop the bubble and ride the Hydro ring up.
78	You can come across this Hydroculus while solving the quest puzzle.
79	Hit the device to summon steps that lead to the Hydroculus.

Three Hydroculi can be found in The Narzissenkreuz Adventure quest line. Check out our guide on this quest here:

The Narzissenkreuz Adventure Quest Guide

Underwater Hydroculus #80 to #82

No.	Image	How to Get
80		Located northwest of the Elton Trench. Destroy the Bullet Barnacles around the area to reveal the Hydroculus.
81		Located northwest of the Elton Trench, just by a teleport waypoint.
82		Hidden under a stone in the waters of a lake north of the Statue of the Seven in the Elynas area.

Hydroculus #83, #84, and #85 in A Brush of Seafoam and Crimson Quest

No.	Image
83	In the area known as ''A Lonely Place,'' on top of a slanted structure.
84	On top of a small rock pile in the Merusea Village.
85	Northwest of ''A Very Bright Place'' on top of a pink house.

Merusea Village has 3 Hydroculi, which can be unlocked through the Brush of Seafoam and Crimson quest line. Check out our guide on this quest here:

A Brush of Seafoam and Crimson Quest Guide

4.1 Underwater Hydroculus

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Hydroculus #129 and #130

No.	Image	How to Get
129		Located south of the Teleport Waypoint, hidden behind a boulder. To obtain it, use the Xenochromatic Jellyfish's ability to destroy the boulder and then swim to it.
130		Can be found in the lake to the right of the Fontaine Research Institute's Statue of the Seven. Dive into the lake, pass through the tunnel, and continue down the road until you reach a big cavern. The Hydroculus can be seen in some ruins to the left.

Hydroculus #131 Locked in Bravais' Secret Study

Found in an underground cave east of the Experimental Field Generator. Collect all Mysterious Ores and create Arkhium Lumenite in the Forging Press under Submerged Stony Path to get access to the cave.

Hydroculus #132 to #146

No.	Image	How to Get
132		Can be found in an underwater ruin northeast of the Fontaine Research Institute Statue of the Seven. To open the ruin's gate, activate the Echoing Conch nearby and then use the Blubberbeast Ability. Defeat the nearby enemies and swim to obtain the Hydroculus.
133		Located slightly east of the underwater Teleport Waypoint, on top of a shattered pillar with an arch.
134		Located underwater, on top of a shattered pillar, just west of the underwater Teleport Waypoint.
135		Located west of the Fontaine Research Institute Statue of the Seven in a submerged tower. Swim to the bottom of the tower and destroy the Deepwater Assault Mek guarding the mechanism. Hit the mechanism once, then enter the tower to obtain the Hydroculus.
136		Located underwater, northeast of the Liffey Region Statue of the Seven, between three large coral platforms.
137		Located in Mont Esus East near the entrance to an underwater cave. Simply dive below and head to the cave entrance to find the Hydroculus.
138		Can be found deep below the underwater tunnel from #137. Simply swim deep into the tunnel and you should be able to see it on the far left side.
139		Located near the entrance of a metal shaft underwater, just below #140.
140		Located immediately south of the underwater Teleport Waypoint, on top of one of the metal structures.
141		Located on top of Meropide's Fortress.
142		Located underwater north of Meropide's Fortress, at the entrance of the cave.
143		Located north of the Fortress of Meropide, floating above seaweed and just past a cave entrance.
144		Can be found in a pool at the far end of the Millennial Pearl Seahorse boss arena from the Teleport Waypoint.
145		Obtainable after completing Unfinished Comedy sub-quest: An Eye for an Eye. After finishing the subquest, return to the map location and get the Hydroculus.
146		Follow the underwater tunnel from the Millennial Pearl Seahorse until you get to the other end where a Hydroculus is floating above the water.

Hydroculus #147 in the Submerged Stony Path

Find the trail heading north from the Teleport Waypoint near Hydroculus #146 and dive into the water. Open the gate with the Xenochromatic Jellyfish ability, then go inside and use the ability to hit the crystal from a distance to open the next gate. Continue along the trail until you reach the Hydroculus.

Hydroculus #148 and #150

No.	Image	How to Get
148		Can be found on top of a massive fan inside Kuisel's Clockwork Workshop, complete the Road to the Singularity quest to unlock. Just climb a nearby ladder and glide towards it.
149		Follow the path south from #146, dive underwater, and continue until you reach a metallic tunnel. A Hydroculus floats in the midst of a chamber, with a Clockwork Meka in the center.
150		To unlock the Terminal, defeat the Clockwork Meka and interact with it to open the gate. Continue south and descend to the lower east levels of the enormous room, where the Hydroculus is located.

4.2 Underwater Hydroculus

No.	Image	How to Get
158		Dive underwater in the Weeping Willow of the Lake and swim north side. Destroy the Red Meanies to open up the path that will lead you to the Hydroculus.
162		Located east of the Weeping Willow of the Lake. Enter on the east side of the willow tree. You will see a cannon guarded by two Hilichurls. Use it to break the wall to reveal the Hydroculus.
168		Located inside an alcove found underneath an underwater path in Erinnyes. This path is accessible after cleansing the Root-Consuming Tumor during the Wild Fairy of Erinnyes quest.
172		Located inside the submerged cavern in Erinnyes. This cavern is accessible during the final quest of the Wild Fairy of Erinnyes.
175		Can be found beneath the tiny lake south of the Weeping Willow of the Lake waypoint; simply hit the shell to get the oculi inside.
179		Complete the puzzle/question at the rusty rudder to use the cannon and break the wall. Answers: 1. 3 tables 2. 3 employees 3. Romaritime Flower
180		Can be found on a small pool of water inside the cave entered from 179.
189		Found within a sunken ship north of the Fort Charybdis ruin waypoint.
191		Located in Fort Charybdis Ruins, floating above the golden gears. Climb one of the gears to your left. Reaching the top of the nearby shaft will summon a wind that will take you to the Hydroculus.
192		Similiar location to Hydroculus 191. Solve the Seelie puzzle to open up the underwater section of the area.
194		Located underwater just by the Morte Region Statue of the Seven. The Hydroculus is located inside the ruins where a Bubbler Seahorse resides.
196		Can be found during the Search in the Algae Sea quest; in the same room as Hydroculus #197 but behind a large mechanism on the far side.
197		Can be found during the Search in the Algae Sea quest; follow the path on the right side of the underwater teleport waypoint.
198		Can be found during the Search in the Algae Sea quest. Locked behind a red barrier, but you can reach it through the doorway by the nearest teleport waypoint.
201		Found during the Cupid's Lover seal. Once inside the Orthant's chamber, go deep into the room where the piece is situated. There should be a looking glass inside. Use it to teleport out of the room. You will reappear within a corridor, carrying the Hydroculus and the special key.
202		Located at the entrance of the underground area in the East Slopes of Mont Automnequi.
203		Can be found underwater in ruins south of the Morte Region. You can simply swim up to it.
205		Located on an underwater arch north of the East Slopes of Mount Automnequi.
206		Located underwater, east of the East Slopes of Mont Automnequi teleport waypoint.
208		Can be found underwater to the north of the tower waypoint. Hydroculus can be obtained by destroying the massive rock.
209		Can be found just to the left of the surface waypoint of the Fort Charybdis Ruins.
211		Located by the west entrance of Fort Charybdis Ruins. The Hydroculus will be close by the shore.
212		Located underwater south of the west entrance of the Fort Charybdis Ruins. The Hydroculus is floating under a ruined underwater bridge.
213		Can be found beneath an underwater cliff southwest of the Fort Charybdis Ruins, near a seaweed clump.
214		Located floating above the east entrance of Fort Charybdis Ruins.

4.6 Sea of Bygone Eras Hydroculus

Click here to open 4.6 underwater map in new tab

The majority of the underwater hydroculus in 4.6 can be found within the Sea of Bygone Eras. Unlocking these areas require travelers to complete parts of the Canticles of Harmony quest in order to gain access.

No.	Image	How to Get
226		Found directly beneath the Teleport Waypoint, inside a tiny cavern in the Path of the Ocean Pillars.
227		Located on top of the first Nameless Stone Statue in the Caesareum Palace Cave. It should be at the tip of the blade.
228		Located on top of the blazing door in the center of the Caesareum Palace.
229		Hidden behind breakable rocks inside the Caesareum Palace.
230		Located at the entrance of the Caesareum Palace Cave, which lies near the sea floor, past a big, bright, pink coral with blue seaweed coming out of it.
231		Located south of Initium Iani, inside a crevice near the Recovery Orb fish.
232		Found on top of a broken golem statue in Porticus Anticus.
233		Found inside the big bell in Portus Anticus. Use the Aqua Current to easily get to the Hydroculus.
234		Located north of Initium Iani on the higher part of the stone tower.
235		Found on the lower level of Portus Anticus, on top of a Golem Statue near some blue corals.
236		Located on top of a cliff, with a line of floating rocks nearby.
237		Located on top of the Stone Pillar west of the waypoint, surrounded by huge pink mushrooms.
238		Located near the Teleport Waypoint in Initium Iani, beneath some blue corals.
239		Found on top of a stone pillar in Initium Iani.
240		Found underneath the giant yellow plant in Initium Iani.
241		Found inside a square crevice with a blue green coral inside.
242		Found at the top of the cliff south of Initium Iani. Located near the enormous blue seaweed.
243		Located between two stone pillars in the Sea of Bygone Eras.
244		Found on top of a giant pink mushroom in Sea of the Bygone Eras.
245		Located north of Hortus Euergetis, behind a crevice behind a massive glowing flower.
246		Located north of Alta Semita near the waypoint, on top of a small stone pillar.
247		Found on top of a cliff near Alta Semita, next to a large plant.
248		Found within a clam on top of a pink mushroom south of Alta Semita, near the waypoint.
249		Located south-west of Clivus Capitolinus, near the broken bridge. You can find the Hydroculus on top of the huge orange mushrooms.
250		Can be found on top of blue corals surrounded by Fontemer Aberrants in Collegium Phonascorum.
251		Located between metal pillars inside the Collegium Phonascorum.
252		Found in Collegium Phonascorum, surrounded by a force field and guarded by two Aurum Angelfish.
253		Can be found on top of a broken pipe between Alta Semita and Collegium Phonascorum.
254		Found within a damaged pipe in the center of Alta Semita.
255		Found under a breakable rock pile at the very bottom of alta semita; smash the boulders using the nearby fontemer crab.
256		Can be seen north of Alta Semita, on top of a stone pillar next to a large plant.
257		Located behind a breakable rock. You can get the ability from the Aberrant nearby and use it to destroy the rock.
258		Located north of Alta Semita on a small stone platform over the bridge.
259		Found north of Alta Semita, between two Allochromatic Anemones under the bridge.
260		Located north of Clivus Capitolinus, inside a large clam on a pink mushroom attached to the pillar.
261		Can be found near the end of the bridge leading to the Clivus Capitolinus entrance.
262		Found east of Alta Semita on top of a Washer Octopus, which is near three Allochromatic Anemones.
263		Located east of Collegium Phonascorum, on top of a large blue plant.
264		Located south of Clivus Capitolinus, atop the smaller stone pillar on the huge pink mushroom.
265		Located south of Clivus Capitolinus, beside a treasure chest guarded by a Fontemer Crab.
266		Located south of Clivus Capitolinus, between the broken pillars near the teleport waypoint.
267		Located south-east of Clivus Capitolinus, inside a breakable rock. You can use the Aberrant Crab's abilities to destroy the rock.
268		Located on top of a tall, shattered pillar in the cave beneath the Clivus Capitolinus, in the same place as the Local Legend, Cineas.
269		located inside the narrow opening on the top of the Clivus Capitolinus Building.
270		Use the elevator within the Domus Aurea after defeating the boss in the Fortune Plango Vulnera quest.
271		Located on the stairs inside the Doumus Aurea. To access the location, complete the final part of the Canticles of Harmony Quest Chain.

How to Use Hydroculus

Upgrade Fontaine's Statue of the Seven

Like all other oculi, the Hydroculus is used to upgrade the Statue of the Seven in Fontaine! Upgrading the Statue of the Seven rewards you with Primogems, Shrine of Depths Keys, and Adventure EXP.

How to Level Up Statues of the Seven

How Many Hydroculus are There in 4.6?

There are 271 Hydroculus total found in the Fontaine region as of Version 4.6, meaning you can upgrade the Statue of the Seven in Fontaine up to its maximum level 10! You may also have 1 Hydroculus left over in your bag afterwards.

Search with Friends

If you're finding it hard to explore the various areas of Fontaine, bring a friend or two to help you! Check out our friend request and co-op boards for potential exploration buddies:

Genshin Co-Op Boards
Friend Request Board	Co-Op Board	Supporting Cast Board

Rewards from Fontaine Statue of the Seven

Lvl.	Hydroculus Required	Rewards
2	20	Mora x800 Primogem x60 Hydro Sigil x5 Fontaine Shrine of Depths Key x1
3	22	Mora x1200 Primogem x60 Hydro Sigil x5 Memory of Running Stream x1
4	25	Mora x1600 Primogem x60 Hydro Sigil x5 Fontaine Shrine of Depths Key x1
5	28	Mora x2000 Primogem x60 Hydro Sigil x10 Memory of Running Stream x1
6	30	Mora x2400 Primogem x60 Hydro Sigil x10 Fontaine Shrine of Depths Key x1
7	32	Mora x2800 Primogem x60 Hydro Sigil x10 Memory of Running Stream x1
8	35	Mora x3200 Primogem x60 Hydro Sigil x15 Fontaine Shrine of Depths Key x1
9	38	Mora x3600 Primogem x60 Hydro Sigil x15 Fontaine Shrine of Depths Key x1
10	40	Mora x4000 Primogem x60 Hydro Sigil x15 Fontaine Shrine of Depths Key x1

Note that players who have not reached Adventure Rank 60 can still gain Adventure EXP instead of Mora from the Statue of the Seven.

Tips on Finding Hydroculus

Use Resonance Stone Gadget to Detect Missing Hydroculus

Above shows the range of the Hydroculus Resonance Stone, which works similar to all the other Resonance Stones in the game.

Players can use the Hydroculus Resonance Stone to help collect Hydroculus! After crafting a Hydroculus Resonance Stone, go to your Inventory and select to use it. The map will then pull up and show you an approximate area where a Hydroculus is located.

Get from Fontaine Reputation System

You can get the crafting recipe for the Hydroculus Resonance Stone once you reach Reputation Level 8 in the Fontaine Reputation System.

Oculus Resonance Stone Guide

Genshin Impact Related Guides

All Interactive Map Guides

Map Guides for Teyvat Nations

List of Region Map Guides
Mondstadt Map Guide	Liyue Map Guide
Inazuma Map Guide	Sumeru Map Guide
Fontaine Map Guide	Natlan Map Guide

All Nations and Regions

Map Guides for Other Areas

List of Map Guides
Enkanomiya	Golden Archipelago
Dragonspine	The Chasm
Sumeru Rainforest	Sumeru Desert
Veluriyam Mirage	Chenyu Vale
Simulanka

Oculi Location Guides

Teyvat Oculus Guides
Anemoculus	Geoculus	Electroculus
Dendroculus	Hydroculus	Pyroculus

Other Oculus Map Guides

Dendroculus Guides
Rainforest Dendroculus	All Desert Dendroculus
Hadramaveth Dendroculus	Girdle of the Sands Dendroculus