After taking care of the raptor on the far bank of the piranha pool, enter the building through the gate you just opened.

The gate closes behind you, and there's another raptor lurking inside. Run in and jump up on the low block on the right side of the dark room.

The raptor can't reach Lara here, so you can shoot it from above with pistols.

There are 3 switches in this room. Any one of them will open the gate so you can exit, but In order to open the wooden trapdoor in the ceiling, you'll need to pull all of them. Two of the switches also let in more raptors. If you'd rather not fight them up close in this dark space try this:

Pull the first switch (closest to the entrance) and immediately roll.

Run past the raptor, and jump onto the block.

Then shoot the raptor before moving on to the next switch.

If it runs out of the room, hop down to the floor on the side of the block away from the door, wait for it to return, and then hop back up and keep shooting.

Pull the second switch (in the corner opposite the entrance). This doesn't appear to do anything, but it's necessary to open the trapdoor.

Finally, pull the third switch (in the far right corner near the small alcove) to open the trapdoor and let in 2 more raptors.

Immediately hop back once...

...then backflip onto the block.

Now you can take your time shooting the dinosaurs.

[Part 2 | Part 4 | Return to the Crash Site Walkthrough]