Get down at the handsome neoclassical palace, with an enlightening historical tour of its amazing light wells – plunging stone crevasses which run along three sides of the famous central courtyard, two storeys below ground. Brave souls can also poke around the spooky subterranean ‘Deadhouse’, which feature preserved seventeenth-century gravestones.
Thu 1.15pm and 2.45pm; Sat hourly 12.15pm-3.15pm. Free.