Grace Cathedral is an Episcopal cathedral on Nob Hill, San Francisco, California. It is the cathedral church of the Episcopal Diocese of California. The cathedral is famed for its mosaics by Jan Henryk De Rosen, a replica of Ghiberti's Gates of Paradise, two labyrinths, varied stained glass windows, Keith Haring AIDS Chapel altarpiece, and medieval and contemporary furnishings, as well as its forty-four bell carillon, three organs, and choirs.