Westerplatte is a long peninsula at the entrance to the harbour. When Gdańsk became a free city after WWI, Poland was permitted to maintain a post at this location, at the tip of the port zone. It served both trading and military purposes and had a garrison to protect it. WWII broke out here at dawn on 1 September 1939, when the German battleship Schleswig-Holstein began shelling the Polish guard post. The garrison, which numbered just 182 men, held out for seven days before surrendering.
The site is now a memorial, with some of the ruins left as they were after the bombardment, plus a massive monument put up in memory of the defenders.
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.