Built between 1215 and 1263, the cathedral is an earlier Italian building. The exterior and interior of the cathedral consist of white and dark green marble, alternately striped, and black and white is the symbol of Siena. A second large-scale expansion of the main body of the cathedral was planned in 1339, but the Black Death pandemic in 1348 led to the shutdown and the work was never resumed. What can now be seen is the exterior wall of the southern cathedral. You can climb one of the walls through narrow stairs to enjoy the city view.