Kuqa's Great Mosque, rebuilt in 1932 on the site of a 16th-century original, is the second largest in Xīnjiāng. (The largest is the Id Kah Mosque in Kashgar.) It's a wonderfully quiet and meditative space, with a huge and ornately painted colonnaded prayer hall that makes for a pleasant refuge from the heat of the day. There's a small museum with a gift shop on the premises, too, which is mainly worth peeking into for its interesting old-town views.