The first mention of the Ludza Castle dates from 1433 when the Livonian Order built a large and strong fortress to replace an earlier wooden fortress built by the ancient Latgalians. The Ludza stone castle had three stories, six towers, three gates and two foreparts. It was built as an outpost for the Livonian order, mainly to strengthen the eastern border of Livonia and guard trade routes from Russia.
In 1481 the Russians invaded Livonia, occupied and devastated the castle. Only the 1525 through improved relations with the Grand Duchy of Moscow, the Livonian Order rebuilt the castle only to see it destroyed again in 1654 by Russian troops under orders from the Russian tsar Aleksey. At the start of the Livonian War in 1558, German troops attacked Krasnij Gorodok and destroyed a number of parishes in Pskov. In the same year Maskavijas troops of Gregory Temkina occupied the castle, but suffering defeat, he was forced to abandon his conquest.
In 1577 Livonia was once again invaded by Russian troops under the guidance of Ivan IV Vasilyevich and the castle was sacked. The following year the Order had Ludza castle with some others in the Grand Duchy of Lithuania mortgaged, and in 1561 asked the castle to be included in the Inflantia. In 1582 the castle returned to the Polish-Lithuanian Commonwealth.
During the Polish-Swedish War in 1625 the Swedish army occupied the castle, but the Polish-Lithuania Commonwealth soon got it back. In the Russian-Polish War in 1654 the Russian Voivoda Lev Saltikovs surrounded Ludza and the castle surrendered. According to a decision of the Polish Sejm in 1667, only the Daugavpils castle was maintained and other defenses, including Ludza castle, was neglected. After that the castle was abandoned and left in ruins.
Nowadays the impressive fragments of the castle walls, including a three-floor high fragment, still remain. The ruins are the main tourist attraction in the Ludza District, and is considered a symbol of the town.
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.