I am having trouble finding the key to open door off of water room.

I have jumped the lava and worked my way up the rocks and come back through to the water room and pushed button to open gate however when i expored the room where the gate went up i noticed you need a key and i have no idea where to find it.

The 'X' on the map guides to a ledge but i cannot get up ledge from water as it is too high.

Any help would be appreciated

THANKS

Hi,
I've red my walkthrough and I found 2 keys to pick up, the first one is the Shell Key wich you can find on the body in the barge in the pool, the second one you use to free Sophia and that one you can find: you have to take an elevator wich you activated to press a device with a green light. You have to kill the guards by blowing up the barrel next to the cliff. There you find a doorway where you use Urgon's part to crumble it. You will find a blue gem there. Jump down, go out and down the stept and jump the narrow lava flow. Turn right and walk to the edge. Turn around and climb down the ladder there. Follow the path around and engage some more soldiers. besides what's on the bodies you can get submachine gun ammo, three grenades an the second key: the aluminium key. I hope you can do your thing with this answer. Succes

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