A watchtower, or "Diaolou" built by the Qiang people in Sichuan province. Between 10 and 30 meters high, the watchtowers were normally built beside lower houses. The Qiang ancestors built them to store grain and offer shelter during wars.  While in Kaiping city of Guangdong province, about 1,800 castle-like towers dot the landscape. Some of the towers date to the Ming dynasty. Others were constructed in the early 20th century and bear obvious Western influences. They received a UNESCO World Heritage Site listing in 2007. [Photo/CFP]