Nanjing City, Jiangsu, China

5. Historical Remains of the Old Stone Wall

Nanjing enjoyed its golden years under the Ming, and there are numerous reminders of the period. One of the most impressive is the Ming city wall measuring over 33 kilometers -- the longest city wall ever built in the world. About two-thirds of it still stands. It was built between 1366 and 1386 by more than 200,000 laborers. The layout is irregular, an exception to the usual square walls of the times, as much of it is built on the foundations of earlier walls that took advantage of strategic hills. Averaging 12 meters high and 7 meters wide at the top, the wall was built of bricks supplied from five Chinese provinces. Each brick had stamped on it the place it came from, the overseers' name and rank, the brick-maker's name and sometimes the date. This was to ensure that the bricks were well made; if they broke they had to be replaced.