The Desert of Doom (also referred to as the Desert Lands) is an area of Ooo that is thought to be very dangerous. In "The Other Tarts," Finn and Jake transport the royal tarts through this desert and run into a number of its inhabitants including Grimby, Taddle, J.J., Chuds, and a Butterfly With Laser Gun. They also run into apparently dangerous, blind zombies in a dark cave, so for the short while, it is seen that the Desert of Doom lives up to its name. The land here is covered with rock formations and a surprisingly large number of wrecked ships, indicating that the desert might have been underwater at one time, before the Mushroom War. There are also large amounts of whale skeletons.
The Desert is located near the Bad Lands, separated by a mountain range.
The desert was seen again for the first time since season two in the season four episode "Five Short Graybles," when Finn and Jake were going to have a "super ultimate high-five." Jake uses the whale skeleton to slingshot himself with his Stretchy Powers.
The Breakfast Kingdom might be located in the Desert of Doom, since it is located in a similar fashion to the desert and has a mountain range that separates the Bad Lands from the desert behind it.