The Imam Reza shrine  in MashhadIran is a complex which contains the mausoleum of Imam Reza, the eighthImam of Twelver Shi'ites. It is the largest mosque in the world by dimension and the second largest by capacity. Also contained within the complex are the Goharshad Mosque, a museum, a library, four seminaries, a cemetery, the Razavi University of Islamic Sciences, a dining hall for pilgrims, vast prayer halls, and other buildings.

Every year the ceremony of Dust Clearing is celebrated in the Imam Reza shrine.