Start by hopping into the water and swimming to the wooden platform ahead.
Climb out and begin climbing the wall. Grab the wooden ledge and then jump
away from it to get onto a platform. From here, just make your way across the
room by going from one side to the next. Activate the lever and then run
through the gate.
Head into the following chamber and drop into the water. Swim toward the big
iron gate and hold X to dive underneath and get to the other side. Proceed
north from here. You can climb these walls pretty easily. Just climb one side,
then jump away from the wall to the opposite one and repeat. Continue on to the
top where you'll get a quick little tour of the next area.
After that, Ledge Assassinate the guard here and climb out. As you proceed over
to the other side of the room, you'll attract more guards. A lot of them are
easy to deceive though and kill off stealthily.
Dispatch all the guards and then go into the southwest corner of this area.
Climb the scaffolding of some sort and use it to jump to a balcony. Go to the
east wall and climb onto the crate. Jump up and grab onto the red shield. Jump
away from this to reach another balcony.
Here you'll find the second lever and the camera will show you the third. Throw
this lever then quickly proceed north, hopping the gaps effortlessly to get to
the next one before the gates shut. Interact with this lever and it's the same
thing; move fast to make it to the other side.
Go around the corner using the beams and you'll see a large gap. Climb the east
wall and then shimmy over to the left using the shields and windows. Get over
to the open window and drop down to enter.
Go down the stairs then climb over the railing up and to the left. Kill the
two guards here then take the stairs down. You'll encounter two more guards and
a Brute. Disarm the Brute and kill him, then deal with the others easily.
Find the large wooden wall/fence in the southeast corner down here. Climb the
platform next to it to get up here. Now from here, you can make your way
clockwise around the room to the platform where you saw the exit earlier. Just
climb the shield and shimmy over to the one on the left to climb out of here.
You'll find a lever here. It operates a gate to the far left. It gives you
some time, but not much, to get there. First figure out how you're gonna get
there. Turn left and face that northeast corridor. You can see a broken wall
on the right side. This is where you begin after throwing the lever. Climb up
that, then jump to the left side wall. You'll walk out onto a beam, climb the
column, then jump away from it to reach a wooden platform. The door is then
just a beam and a swing bar away.
Provided you make it in time, you'll reach the tomb on the other side. As
usual, plunder the place of its goodies, ending with the seal from the
sarcophagus. The exit is a trap door to the left.