The Castle of Guimarães was built under the orders of Mumadona Dias in the 10th century to defend the monastery from attacks by Moors and Norsemen. At the end of the 11th century the castle was heavily expanded and remodeled, under the direction of Count Henry, to act as his residence. The castle became the official royal residence from 1139, when Portugal became independent from the Kingdom of León, until circa 1200.
Between the end of the 13th and beginning of the 14th century, the castle was remodelled by King Denis, resulting in the form that stands to this day. In 1369, King Henry II of Castile invaded Portugal and encircled the castle of Guimarães, but was defeated by its population and forces. Sometime between 1383 and 1433, the two towers that flank the main entrance were order built by King John I of Portugal.
After the castle's demolition was abandoned in the 19th century, many of the houses, estates and lodgings around the castle were expropriated. The first attempts at restoration occurred during the mid-20th century.
Today Guimarães castle area is delineated by walls forming a pentagram, similar to a shield, that includes eight rectangular towers, military square and central keep. Originating in the foundations of a Roman structure, from the writings of Alfredo Guimarães, it was later elaborated on the French model, in its current the form of a shield, with reduced central yard and difficult accesses. It includes several Gothic characteristics, owing to its remodelling at the end of the 13th century, when the keep and residences were constructed (possibly over pre-existing structures).
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.