Where is the Lost River in Subnautica?

The Lost River in Subnautica is one of the main biomes, and it's not easy to find. Present deep below the surface, this dark green area can be accessed through both the northern and southern entrances on the map. However, getting there will require the right amount of preparation.

With only hostile creatures like Ghost Leviathans nearby and depths dropping way past 900 meters, this is no swim in the park. So, here's how to locate the Lost River in Subnautica.

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How to reach the Lost River in Subnautica

Glimpse from the Lost River in Subnautica (Image via Unknown Worlds Entertainment)

Items required

Before even thinking about heading to the Lost River in Subnautica, you’ll need a Seamoth with a Depth Module Mk III to survive the descent. Without it, your vehicle simply won’t make it beyond 900 meters. On top of that, bring a high-capacity O2 tank, a Seaglide, and Fins to maneuver quickly. A repair tool is also essential since your Seamoth is likely to take hits along the way.

Stock up on food, water, and first aid kits, too, as the trip is long, and you might not resurface for a while.

Northern route to the Lost River

The northern entrance is the most straightforward path. Start near the Safe Shallows, where the two giant coral tubes rise above the water close to the kelp biome. The coordinates are (-36, 0.3, -38). From there, set your course between north and northwest, aiming for the middle.

As you travel, you’ll cross the Grassy Plateaus before coming across a massive rock formation. Beyond it lies a large drop leading deeper into the world. Follow it down, and at coordinates (-578, -433, 1257), you’ll spot a thick, tree-like root. Head in that direction, and you’ll find yourself inside the Lost River biome. Once you’ve gone this way once, you’ll see how direct and memorable this route is.

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Southern route to the Lost River

The southern entrance is trickier. From the same coral tube starting point, head about two clicks southwest. The coordinates here are (-74, 2, -163), placing you around the Grand Reef or, more accurately, the Deep Grand Reef.

This path isn’t as obvious. Look out for what feel like “nostrils” or natural openings in the terrain. Drop into one of these and keep pushing between north and northeast. You’ll weave through a sub-cave system, and after descending far enough, the tone will shift, the water will glow differently, the music will change, and you’ll know you’ve entered the Lost River in Subnautica.

It’ll be disorienting at first, but you'll eventually recognize the biome's green haze.

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