Belém Tower, or Torre de Belém, is a 5-storey fortified lighthouse located in the Belém district of Lisbon, Portugal. It was constructed between 1515 and 1521 on the orders of Manuel I (1515-1520) in order to defend the port at Belém, as well as the nearby Mosteiro dos Jerónimos. The tower stood on an island in the middle of the River Tagus until the course of the river was diverted by an earthquake in 1777; the tower had previously survived the 1755 Lisbon earthquake. It is classified by UNESCO as World Heritage site.
The Torre de Belém was designed by Diogo and Francisco Arruda in the Manueline style - it is, in fact, Portugal's only example of a purely Manueline building. Among the decorations featured on the tower are Manuel's badge of honour (an armillary sphere) and a cross of the military Order of Christ (the successor organization to the Knights Templar in Portugal), who participated in many Portuguese conquests.
The tower has seen use as a prison, both by Spanish conquerors and by Dom Miguel (1828-1834). In 1807, French troops destroyed the top two storeys, but these were later rebuilt.
Within the tower, visitors can see the dungeons or enter the "whispering gallery", as well as climb up to a 35 m high platform which offers views of the Padrão dos Descobrimentos.
The tower was the departure point for explorers to the rest of the world in the sixteenth and seventeenth centuries.