The Collegiata di Santa Maria Assunta or Duomo di San Gimignano is a Roman Catholic collegiate church and minor basilica in San Gimignano, in Tuscany in central Italy. It contains important cycles of Renaissance frescoes by artists including Domenico Ghirlandaio, Benozzo Gozzoli, Taddeo di Bartolo, Lippo Memmi and Bartolo di Fredi. It falls within the UNESCO World Heritage Site of the "Historic Centre of San Gimignano", with its frescoes being described by UNESCO as "works of outstanding beauty".