The Ponttor is one of the two remaining gates of the original city wall of Aachen. It was built in the 14th century and manned by soldiers and militia throughout the Free Imperial City of Aachen era. Today, the Ponttor is used by German Youth and Scout groups.
The Ponttor was constructed as a right-angled three-stock tower castle. In the main entrance, there is a Portcullis as well as a machicolation, through which things could be dropped on invading forces. A bridge passage with crenelations spanned a moat and was strengthened in the foregate with two reinforced towers (barbicans). The building material was Devonian sandstone, Pennsylvanian carbonite sandstone and quartzite, with the framing material made of light bluestone.
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.