BEIJING, Aug 15 (Reuters) - One of the world's largest and most famous ramparts, the wall surrounding the ancient Chinese city of Xi'an, is suffering serious subsidence after days of downpours, state media said on Wednesday.

Seven sections of the 600-year-old city wall in the northwestern city, famous for its Terracotta Warriors, have been seriously undermined by rain since last month, the China Daily said.

"Accumulated water collected in some low-lying areas of the wall ... and infiltrated the wall and made the inner soil subside," Sun Xinchang, engineer of the City Wall Administrative Committee, told the newspaper.

A newspaper picture showed a long crack on the west gate of the vast wall, one of the few remaining in China.

"If urgent repairs are not carried out, some parts of the ancient wall will collapse," Fan Dake, deputy director of the committee, was quoted as saying.

The Xi'an city wall, built at the beginning of China's Ming Dynasty, is 13.75 km (8.5 miles) long, 12 metres (39 ft) high and up to 14 metres wide across the top.

Most ancient Chinese towns of a significant size were protected by vast city walls, with gates at each point of the compass, but many have since been knocked down either because they no longer served a purpose, they represented an old, feudal China, or because of city planners' rush to develop.

Beijing's historic centre and city walls were knocked down after the Communists came to power in 1949 to make way for a ring road, the concrete expanse of Tiananmen Square and the monolithic Great Hall of the People.

AlertNet news is provided by