Museo Nacional Centro de Arte Reina Sofía in Madrid

You're standing at the Reina Sofía, Spain's national museum of twentieth-century art, named after Queen Sofía. Start with the building itself. That long, stern façade wasn't made for a museum. It was a hospital. King Ferdinand the Sixth had it built in the eighteenth century, because Madrid's old hospitals had become too small. Architects José de Hermosilla and then Francisco Sabatini worked on it for years, and in the end only a third of Sabatini's plan was ever built. The hospital didn't close until 1969.