Belém Tower 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 defence system at the mouth of the Tagus river and a ceremonial gateway to Lisbon.
The tower was built around 1514 by Francisco de Arruda and is a prominent example of the Portuguese Manueline style, but it also incorporates hints of other architectural styles. The structure was built from lioz limestone and is composed of a bastion and a 30-metre, four-storey tower. It has incorrectly been stated that the tower was built in the middle of the Tagus and now sits near the shore because the river was redirected after the 1755 Lisbon earthquake. In fact, the tower was built on a small island in the Tagus River near the Lisbon shore.
References:The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.