Ox Street Mosque or Cow Street Mosque (Niu Jie Qingzhensi) was first built in 966. It was destroyed in 1215 by Genghis Khan. Reconstruction of the mosque occurred during the reign of Qing Emperor Kangxi (r. 1661 - 1722). The mosque has all the usual features of mosques found elsewhere in the world minaret, prayer hall facing Mecca, Arabic inscriptions the buildings themselves are distinctly Chinese. It remains Beijings largest and oldest mosque.