The famous 16th Century Torre de Belém was a fortified tower built at the time of Portugal’s Age of Discovery to defend the entrance to the river Tagus and Lisbon. Originally, it stood some way from the coast but the silting up of the estuary and land reclamation have placed it just a stone's throw from the bank. Although built in the classic Manueline late-Gothic style, much of the decoration now visible was added when the tower was renovated during the reign of Queen D. Maria II in the 1840s. The Tower of Belém is classified as a UNESCO World Heritage monument.