Sakkara Circle

The Sakkara Circle is a dead end "circle" in the Valley of Tears. The best way to reach it is to take the Portal Room, the X is the drop location and the star is the Sakkara Circle (click the mini-map to enlarge it):

The Sakkara Demons give amazing experience and there is a large group of JUST them in the Circle which makes this one of the top leveling places. It is also a pretty short walk to re-spawn the area, just go down to the X below and back :

There are a number of enemies that you will meet walking back and forth from the Circle to re-spawn it, Hell Golems, Hell Golem Warriors, Shadow Guards and of course be careful of the Cerebropods! You might even come across a few random Sakkara Demons before you reach their circle: