The Koppelpoort is a medieval gate in Amersfoort. The gate was built between 1380 and 1425 as part of the second city wall. The whole wall was completed around 1450. The gate was attacked in 1427 during the siege of the city, but this attack was repelled.
The gate was opened and closed every day by the appointed 'wheel-turners'. A minimum of twelve wheel-turners were collected morning and evening by several guards. It was an extremely dangerous task; if they did not begin walking simultaneously, then one could fall, dragging the rest along with often fatal results. Before the gate could come down, it had to be raised, to pull out the iron pins that held it in place. Only then could it come down. While the gate was going down, walking in the wheel grew ever easier and faster, and many people stumbled and broke their limbs. The koppelpoort was also never breached.
The Koppelpoort was given its current appearance during the restoration by Pierre Cuypers in 1885 and 1886. Among other things, Cuypers removed a step between the two gates and replaced it with a slope.
The latest restoration was completed in 1996. It was carried out very cautiously, and with respect for the old building materials.
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.