Run ahead and dive through the gap.
Collect the Ottoman Seal on the table.
Get back out.
Kill the two baddies.
Enter the other room.
On the left you can climb onto the scaffold.
Climb to the upper part.
Stand at the left of the outer edges and look ahead.
There is a lantern from which you can swing.
Get the whip out and take a running jump.
Swing onto the next scaffold.
Walk to the right and take a running jump onto the next scaffold.
Run to the end and step through the entrance.
Turn around and climb up.
On the upper level walk back through the archway.
Turn left.
Take a running jump onto the next platform. (See picture)
Climb down onto the scaffold and step into the entrance.
Use the whip to get to the other side.
Run through the passage and carefully drop down into the next chamber.
Kill the two baddies.
Collect their rifles.
Fill up your water at the fountain.
In the area on the right is a third guy guarding a lift.
Kill him and the two that appear.
Step into the lift and use the switch.
Get out at the top.
Run into the cave and towards the metal crane on the right.
Climb up the ladder.
Get out into the control room.
Use the levers there to navigate the crane and pull the giant head up, so that it's at the top of the crane just above the pit.
Two guy will appear.
Kill the two and climb up the ladder.
Run to the front side of the crane and climb further up.
At the end get out the whip and take a running jump.
Swing over to the head and jump onto it.

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