Roof patches used for well-salt production are seen along the Lancang River (also known as Mekong River in Southeast Asia) in Markam county of the Qamdo prefecture, Southwest China's Tibet autonomous region, on Saturday Oct 16, 2010. Villagers of the local Naxi ethnic group drill wells on the hills along the river, collecting salt water which is carried to the roof patches to dry out naturally, giving the well-salt a poetic name, "a sunshine and breeze work". The practice, dating back to the Tang Dynasty (AD 618-907), has become a tourist attraction in recent years. [Photo/Xinhua]