The Flooded Vault

 is a challenge tomb in Tomb Raider.

Location
The Flooded Vault is located on the Shipwreck Beach in the part that can be accessed with Compound Bow, the door leading to it is right after the player crosses the rope from the collapsed tower to the mountains. The door is guarded by couple of Solarii Brotherhood men, and the door must be forced open with the Climbing Axe.

Walkthrough
After opening the door, move to the left and burn the cloth near the raft to release it. Then walk back and take the right path from the door, and blast through the wall with barbed-wire with a shotgun. Use the ropearrows to pull the raft all the way to the opening, then use the raft to jump behind the corner on the right. Use a rope arrow to pull the counterweight on the ceiling, to make the water safe, then cross the water. Pull the raft closer to the electrical socket. Once again pull the thing on the ceiling and then pull the raft under the electric socket. Water now being safe, you can cross it on the left side of the room, climb the stairs and reach the treasure.