Traces of "sao", or a mattress used in dyke construction in ancient times, are seen at the ruins of the No. 1 bridge in the old course of the Weihe River in the northern suburbs of Xi'an, capital of Northwest China's Shaanxi province, Jan 16, 2015. [Photo/cnwest.com]
京公網(wǎng)安備 11010502035176號(hào)