The Muldoon Forest

The Wulong Forest is a geographical feature situated on the coast of the western United Republic of Nations, formerly the Earth Kingdom, and was the location of the final battle of the Hundred Year War between Fire Lord Ozai and Avatar Aang. It is characterized by the hundreds of rock columns that tower over the landscape. The Muldoon Forest is a name given by many nearby villagers, meaning "fort" due to it shedding light on hard times like Winter and Wars that once took place there. It is still known as the Wulong Forest and is now host to criminals and wild animals. It is not known as a "fort" to this day but the villagers found the name fitting.

History
Back In 99 AG, After teaching Aang how to energy bend, the lion turtle left Aang to wait for Ozai's arrival at Wulong Forest where the two would duel. As the latter and his airship fleet arrived, they immediately harnessed the power of Sozin's Comet to amplify their firebending abilities and burn down the landscape. A significant portion of the green forest that laid around the rock forest was destroyed, displacing much of its wildlife.

While Sokka, Suki, and Toph interfered with and sabotaged the airship fleet, preventing more damage from being done to the environment, Aang sought out the Fire Lord in order to have a one-on-one confrontation among the many rock pillars that dot the area of the forest. During this fight, many of these pillars were destroyed by offensive or defensive moves by either party. Eventually, Aang managed to incapacitate Ozai and remove his bending, before using his control over the Avatar State and waterbending to extinguish the massive forest fire that threatened to consume the remaining green forest.

Trivia

 * Wulong Karst is a forest famous for its rock formations in northern China near Dandong, on the Korean border.
 * Zhangjiajie National Forest Park in China's Hunan Province holds rock formations similar to those at Wulong Forest.
 * Wulong Forest strongly resembles the landscape seen in the original opening sequence when Avatar Roku is bending, as well as the place where Team Avatar first encountered Combustion Man.
 * The forest also shares similarities with a location depicted in early concept art, in which Aang is seen airbending above a rock column.