Xian City Walls, China
The Great Wall is not the only historic site of its type in China. The ancient city of Xian, best known as the home of the famous Terracotta Warriors, has its own ancient ramparts. The impressive wall was built in the 1300s. The wall surrounds an area of roughly 6 square miles, and even today it remains one of the most imposing fortifications of any era. Averaging more than 50 feet in thickness, the structure remains almost completely intact. The top of the wall is used as a kind of promenade, with tourists and locals alike strolling along it and taking in the sights of the ancient city from on high. There are ramparts spaced evenly all around the wall and four massive gates that were used to enter and exit the city. Because the walls of Xian were almost completely impenetrable, the only hope for attackers was to break through the gates.