After obtaining secret #3 above the ramp with the rolling spikes, as shown in the previous section, drive on carefully to avoid the deep pit on the right at the bottom of the slope.

When you come to the area where you have to make a U-turn between two pits, get out and investigate the large, L-shaped one.

There's a climbable surface on the pit's south wall and a secret in the little crawlspace near the bottom, just above the spikes.

To get there, stand at the top of the climbable wall, facing away from the pit, and then drop back and grab the edge.

Climb down until Lara's hands are at the top edge of the crawlspace and her feet are dangling free.

Release Action and then quickly press it again to grab the bottom edge of the opening. Before Lara can pull her legs up onto the wall...

...press Duck/Crouch and Forward/Up to pull up into the crawlspace.

- OR -

If you're having trouble with these quick button presses, instead climb down so Lara's hands are clinging to the top edge of the crawlspace. Then climb to the left as far as possible.

Let go and quickly grab the bottom edge of the opening. Lara's legs should now continue to hang free.

Continue to hold Action and press Crouch and Forward/Up to pull up into the opening.

This is SECRET #4 (25/70). You can light a flare if you want to, but note that Lara won't do this if she's crawling on hands and knees. Press draw pistols to make her raise one knee off the ground. Then light the flare.

Crawl farther in to find wideshot shells and normal crossbow ammo. (You'll receive the weapon a bit later on.)

Back out of the crawlspace. When you come to the edge, hold Action and press Back/Down to ease out of the opening and hang from the edge. Do not release Action or Lara will fall into the spikes.

Climb to the right then up to the top.

[KV5 Walkthrough]