Housing some of the most important European artistic monuments, the Roman-Gothic style Cathedral of Siena makes for a meaningful morning. Over a million visitors every year step through these stunning doors - it's just as spectacular as Florence's Duomo.

Get up close to amazing frescoes by the likes of Donatello, Michelangelo, and Pinturicchio. They're all here in what is one of the most important examples of this style of building in Italy, constructed between 1214 and 1263.

See the Duomo Nuovo (New Cathedral) and check out the Piccolomini Library, dedicated to Pope Pius II.

Oh, and don't forget to look down. The floor is an art piece in itself, with 56 scenes engraved in marble, which were carved between 1369 and 1547 by 40 different artists. You'll step lightly, but the complexity is staggering!