Abandoned Mines - Crossing the Canyon and Opening the Doors (Part 2)

Jump down off the ledge and head down the slope past the cart with the winch on it to find a box of supplies near the left wall. Now push the winch cart about halfway down the track...

...so it's lined up with the falling water off to the right.

Go around to the other side of the cart and fire a rope arrow into the bucket...

...attaching it to the winch.

Now crank the winch until the bucket is directly beneath the falling water. If it doesn't line up exactly, adjust the position of the cart on the track until it does.

The bucket fills with water, becoming heavier until it finally falls into the canyon, dragging the cart with it...

...and breaking open the huge doors.

When you regain control after the cutscene, run up the ramp and jump to grab the crane.

Pull up and run forward. Jump across the gap and continue to the end of the crane arm.

As you approach the end of the crane arm, it tilts forward. At the end, jump down to the wide stone ledge below.

In another brief cutscene, Lara almost falls but catches the edge and pulls up.

Continue running forward toward the doorway as all hell breaks loose.

As you approach the doorway, the floor ahead collapses. Jump across the gap to safety.