Fort Nieulay, located along the Avenue Pierre Coubertin, was originally dated to the 12th or 13th century. During the English invasion in 1346, sluices gates were added as water defences and a fort was built up around it in 1525 on the principle that the people of the fort could defend the town by flooding it. In April and May 1677, Louis XIV and Vauban visited Calais and ordered a complete rebuilding of Fort Nieulay. It was completed in 1679, with the purpose to protect the bridge of Nieulay crossing the Hames River. By 1815 the fort had fallen into a ruined state and it wasn't until 1903 that it was sold and improved by its farmer tenants. The fort was briefly the site of a low-key scuffle with Germans in May 1940.
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.