Built in the 14th century, this is one of the oldest and well preserved city walls of China. The wall is 40 feet tall and around 46 feet wide at the top and around 60 feet thick. Covering around 36 sq kilometres, this structure is in itself a work of brilliance. Initially it was built to store huge structure proved to be a guard from the enemy attack. The wall has provision for arrows, which were built to provide arrows during war.