The city of Soria formed in a valley near the castle that defended the Douro Riverbanks on the border between the Crowns of Aragon and Castile. The city was destroyed towards the end of the 12th century when Sancho of Navarre attacked it, therefore a great defensive wall was built to prevent further destruction. The wall defended a surface of 100 hectares that went from the Douro River up to the pastureland known as “La Dehesa”, and also from the castle up to the hill where you can find the Chapel of El Mirón.
The Sorian wall was destroyed by General Durán at the end of the Spanish Independence War to avoid French troops from entrenching in the castle. This is the reason why there are so few remains of this castle and why we can only see part of the tower and some parts of the defensive walls. From the castle, you can see a 360º view of the city and the bridge that crosses the Douro River, and in the Chapel of San Saturio, you can see frescos depicting the castle as it once was.
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.