Lierna Castle is built on a peninsula that protrudes into the lake Como and consists of a group of connected buildings, rather than a single building. The main portion of the current buildings was constructed in the 10th century in Romanesque style upon former Roman ruins. The castle includes the 11th-century church of Saints Maurice and Lazarus (Chiesa dei Santi Maurizio e Lazzaro), associated with the Order of Saints Maurice and Lazarus.
The last military use of the castle was in the mid-16th century by Gian Giacomo Medici, known as 'Medeghino' (the 'small Medici'), who was primarily a mercenary.
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.