Domus Romane of Palazzo Valentini (Le Domus Romane di Palazzo Valentini)

When the 16th-century Palazzo Valentini underwent a major renovation in 2005, the magnificent remains of two ancient Roman villas and thermal baths dating from the 4th century AD were discovered underground. After years of additional excavation, this 20,000-square-foot Domus Romane complex is now open to the public.