The Great Mosque in the Muslim Quarter of Xian. The most prominent is the Main Hall is used five times a day for prayer. The interior, which highlights the turquoise painted ceiling, you can admire ebony engraved verses from the Koran. The complex also features a courtyard in which believers have dinner every night as they reflect on religious matters. When night falls, a multi-colored bulbs decorate the minaret and the wall of the spirits, designed to ward off demons.