This stunningly located castle was built in 1237 but is renowned for its vivid 14th-century frescoes. These are particularly rare, with themes that are drawn from secular literature, including the tale of Tristan and Isolde, as well as depictions of day-to-day courtly life. From April through October, a free shuttle runs from Piazza Walther; alternatively, catch suburban bus 12 or 14.