Now home to the University of Seville, this massive former tobacco factory – workplace of Bizet’s fictional heroine, Carmen – was built in the 18th century and is said to be the second-largest building in Spain after the El Escorial monastery northwest of Madrid.

　　You can wander in at will or pick up an audio guide at the porter's office in the main entrance hall – it's free but you'll need to leave photo ID as a deposit.