Built in 1361, this castle’s moment arrived when the Sienese holed up here for 4 years after their city’s final defeat by Florence in 1555 (ironically, the fortress had only recently been expanded and strengthened by Florence’s Medici dukes). You can wander round the pentagonal walls and scale a ladder to the highest turret for a view across hills and dales all the way to Siena, but do so before you sample wine in the on-premises enoteca, perhaps the only tasting room in the world with ramparts.