Just below the city walls, on the hillside carpeted with olive trees, sits Cortona's tribute to High Renaissance architecture: Santa Maria delle Grazie al Calcinaio. It was built between 1485 and 1513 and is the masterpiece (and only definitely attributable work) of Francesco di Giorgio Martini. He designed it on a Latin cross plan to mark the spot where a worker in a limekiln (calcinaio) saw a miraculous image of the Virgin appear on the rock wall. The harmonious Brunelleschian interior has a rose window in stained glass by the French master of that art, Guillaume de Marcillat, as well as a late-16th-century Madonna and Saints by Florentine artist Alessandro Allori in the right transept.