The exterior of the cathedral is pretty impressive, and if you don’t have a lot of time in Siena, you might not even go inside and just enjoy the outside. Built between 1215 and 1263 on the site of an earlier structure, the cathedral is in the form of a Latin cross with a slight projecting dome and bell tower. The exterior and interiors are decorated in white and greenish-black marble in alternating stripes, black and white being the symbolic colors of Siena.
If you have time to visit the cathedral, you might be tempted to skip it once you realize you have to pay to get in… but it is certainly worth it and, with the pass, it’s actually a great value! The pass gets you into the cathedral as well as the baptistery, crypt and Opera museum and is valid for 3 days so it most definitely worth the 10 euros!
If you’re visiting Siena after having visited Florence and its cathedral, you’re in for a shock! While Florence’s cathedral is immense and its cupola impressive, its interior is pretty spartan in comparison. In Siena, on the other hand, you don’t know where to look. The columns continue the white/black marble striped motif and, if you look up, there are busts of past religious men of Siena looking down upon you. I recommend you take a special look at the pavement: the most impressive and beautiful of the treasures the cathedral holds are on the floor, where the pavement is decorated with the art of mosaics (using various techniques) to create storytelling masterpieces.
The 56 etched and inlaid marble panels were designed by 40 of leading artists between 1369 and 1547, all from Siena except for Bernardino di Betto, known as Pinturicchio who was Umbrian. Completion of the designs took six centuries, the last ones finished in the 1800s. Today, the mosaic panels in the nave and aisles are usually uncovered although protected from passing feet by barriers, but the most precious ones are under the apse and in the transepts and these are generally protected by special flooring since this is where people sit for mass; these are only uncovered in honor of the Palio and a pair of months during the year, often in September and October.