The Houjie Mosque, also known as the Black Street Mosque, is the principal mosque in Tianshui's old city and one of the more architecturally interesting in the Wei River valley. The building blends traditional Chinese mosque forms — timber-framed halls, a gatehouse in the style of a Chinese pavilion — with Arabic calligraphy and Islamic decorative motifs. The result is the typically northwestern Chinese synthesis that visitors who have been to Linxia or Xi'an will recognise, though in a more modest scale.
The mosque serves Tianshui's Hui Muslim community and is active for daily prayers. Non-Muslim visitors are generally received courteously outside prayer times; ask at the gate before entering the main prayer hall. The surrounding lanes of the old quarter retain more of Tianshui's pre-modern character than the city centre.