Belém Tower (Portuguese: Torre de Belém) or the Tower of St Vincent is a fortified tower located in the civil parish of Santa Maria de Belém in the municipality of Lisbon, Portugal. It is a UNESCO World Heritage Site (along with the nearby Jerónimos Monastery) because of the significant role it played in the Portuguese maritime discoveries of the era of the Age of Discoveries. The tower was commissioned by King John II to be part of a defense system at the mouth of the Tagus river and a ceremonial gateway to Lisbon.
The Tower is situated on the northern bank of the Tagus River in the civil parish of Santa Maria de Belém, municipality of Lisbon, accessible at the western end of the Avenida de Brasília. Nearby are the Monastery of the Jeronimos (to the east) and the Fort of Bom Sucesso (to the west), while to the north are the Tower Governor’s residence, the old Governor’s residence for the Bom Successo Fort, and the Chapel of São Jerónimo . The Tower itself is accessible via the Avenida de Brasília and by a small bridge that extends over the water to the structure. The Tower of Belém is isolated along the riverbank, between the dock of Bom Sucesso and Pedrouços, on a basaltic outcropping of rocks from the Lisboa-Mafra Complex.
The interior part of the bastion cave, with a circular staircase in the north, has two contiguous halls with vaulted ceilings supported by masonry arches, with four lockers and sanitary installations. On the ground-floor bunker, the floor is inclined towards the outside, while the ceilings are supported by masonry pilasters and vaulted spines. Gothic rib vaulting is evident in this casemate, the rooms of the tower and the cupolas of the watchtowers on the bastion terrace. Peripheral compartments on the edges of the bunker, allow the individual canons to occupy their own space, with the ceiling designed with several asymmetrical domes of various heights. The ancillary storerooms were later used as prisons.
Two archways open to the main cloister in the north and south, while six broken arches stretch along the eastern and western parts of the cloister, interspersed with square pillars in the bastion cave, with gargoyle facets. The open cloister above the casemate, although decorative, was designed to dispel cannon smoke. The upper level is connected by a railing decorated with crosses of the Order of Christ, while at the terrace the space is guarded by columns topped by armillary spheres. This space could also be used for light-caliber infantry. This was the first Portuguese fortification with a two-level gun emplacement and it marks a new development in military architecture. Some of the decoration dates from the renovation of the 1840s and is neo-Manueline, like the decoration of the small cloister on the bastion.
On the southern portion of the cloister terrace is an image of Virgin and Child. The statue of the virgin of Belém, also referred to as Nossa Senhora de Bom Successo (Our Lady of Good Success), Nossa Senhora das Uvas (Our Lady of the Grapes) or the Virgem da Boa Viagem (Virgin of Safe Homecoming) is depicted holding a child in her right hand and a bunch of grapes in her left.
The tower is about 12 metres (39 ft) wide and 30 metres (98 ft) tall. On the first floor interior of the Tower is the Sala do Governador (Governors Hall), an octagonal space that opens into the cistern, while in the north-east and north-west corners there are corridors that link to the bartizans. A small door provides access via a spiral staircase to the subsequent floors. On the second floor, the Sala dos Reis (King’s Hall) opens to the loggia (to overlook the river), while a small corner fireplace extends from this floor to the third floor fireplace in the Sala das Audiências (Audience Hall). All three floor ceilings are covered in hollow concrete slabs. The fourth floor chapel is covered in a vaulted rib ceiling with niches emblematic of the Manueline style, supported by carved corbels.