San Gimignano is an Italian hill town in Tuscany, southwest of Florence. Encircled by 13th-century walls, its old town centers on Piazza della Cisterna, a triangular square lined with medieval houses. It has a skyline of medieval towers, including the stone Torre Grossa. The Duomo di San Gimignano is a 12th-century church with frescoes by Ghirlandaio in its Santa Fina Chapel.