Introduction to Gaochang Ancient City: Gaochang, an ancient country in the Western Regions. Gaochang Ancient City is located in the Mutugou River Delta at the southern foot of the Flame Mountain, 27 kilometers east of Turpan City. It was built in the Han Dynasty in the 1st century BC and is one of the treasures of the world's religious and cultural gathering places. It is known as "the replica of Chang'an in the Western Regions".