Church of St. Gertrude (Šv. Gertrūdos bažnyčia) is one of the oldest Brick Gothic churches in Lithuania. The exact date when the church was built is unknown, but it must have been in the 15th century. In 1503 Grand Duke of Lithuania Alexander designated the church as a parish church of Kaunas. In the middle of the 16th century a bell tower was attached. The church was damaged in 1655 during the Russo-Polish War (1654–1667). It was rebuilt only around 1680. Around 1750 a wooden hospital was attached to the church. In 1782 it was abandoned for a long time, and at the time there were 5 monks from order of St. Roch residing. In 1796 the church was renovated, organs installed, and living quarters for aparson established. The church was consecrated in 1794.
In 1812 Kaunas suffered from a major fire, which also damaged the church. The hospital was abandoned, and in 1824 transferred to the sister order of Caritas. The monastery was closed in 1864 after the January Uprising. The old hospital was demolished in 1880. In 1921 the church was assigned to the Marianites of Holy Cross and a monastery was built nearby. In 1920 the church was daubed. In 1992 a complex renovation of the church and monastery took place. Since 1991 the Mass is held in the church again, and the Marianites monastery has been returned to the monks.
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.