Chambers of Tulun - From the Citadel Gate to the Trenches

After obtaining the NITROUS OXIDE CANISTER in the CITADEL GATE level, you return to the CHAMBERS OF TULUN through the passageway near Sergeant Aziza.

The Minotaur will be huffing and puffing below, unless you destroyed him earlier using the motorcycle collision bug.

Climb down the ladder to the ground. Turn left and follow the short passage to a raised opening on the left.

Jump to grab the edge...

...pull up, and slide down the other side into the street. Run to the left (north)...

...past the Minotaur. (Or take a leisurely stroll down the street if you killed him before.)

Run around the corner to the right.

Continue past the back door of the CHAMBERS and hop down off the low ledge. The Minotaur won't follow you any farther.

Get on the motorcycle, which should be parked somewhere nearby.

Follow the road to the north, down one hill and up the next, to enter the TRENCHES.

[Citadel Gate Walkthrough]