Han Tui

Han Tui was a city in the Earth Kingdom. It was captured early in the War at the Battle of Han Tui, where Fire Nation forces were commanded by Fire Lord Sozin himself. Although the Earthbenders outnumbered the Fire Army, Sozin was cleverly able to use his enemies' downwind position and the recent drought to burn Han Tui's defenses to the ground in minutes. The Firebenders then moved in on the city and captured it.

The fate of the city afterwards is not known. If it remained inhabited and occupied by the Fire Nation until after the War's conclusion, then it was very likely liberated under the new Fire Lord.