Description: The Qingjing Mosque, literally the Pure and Clean Mosque, was built in 1009 on present-day Tumen Street, covering 2,100 square meters. As the oldest existing mosque in China and well known to the Islamic world, it was designed after the mosque in Damascus of Syria and built with pure granite. Its pointed-arch portal, 20 meters high, has three layers. The outer and middle layers are similar to the caisson ceiling in Chinese ancient architecture. The vaulted inner layer took on the architectural style of ancient Arab. It is clear that architecturally, the mosque is a combination of Chinese and Islamic styles. Standing under the vault, one can realize the time-honored cultural exchanges between China and foreign countries.