San Lorenzo de El Escorial is home to the Monastery of El Escorial, a World Heritage site. This huge complex was built as a monument to commemorate the Spanish victory over the French in the battle of Saint Quentin. Construction lasted 21 years and when it was finished in 1584, the Monastery was the largest building in the world, with 24 km (14.9 mi) of corridors. The building includes a library, Kings' Courtyard, Basilica, and the Palace of Felipe II. The Kings' Pantheon is the burial place for most of the kings of Spain since Carlos I. The Monastery is decorated with works by the most prominent Italian and Spanish painters of the time. Look for works by Titian, Bosch, El Greco, and Velázquez, especially El Greco’s painting of "The Martyrdom of St. Maurice.”