Nuraghe Santu Antine, also known as 'Sa domo de su re' ('The house of the king') is an ancient megalithic edifice built by the Nuragic Civilization in Torralba, one of the largest in Sardinia. It is located in the centre of the Cabu Abbas plain. The main structure was built around the 19-18th century BC, and the other parts of the nuraghe date back to the 17th–15th century BC. The main tower originally reached a height of 23–24 metres and contains three tholoi chambers on top of each other. The central tower with diameter of 15 metres is 17 metres high. Santu Antine is made of huge basalt blocks. It has three floors. The top floor is now gone. Some 27 meters long corridors built with the corbel arch technique can be observed inside of the Nuraghe, superimposed on two floors, the Nuraghe was provided with three wells.
References:Visby Cathedral (also known as St. Mary’s Church) is the only survived medieval church in Visby. It was originally built for German merchants and inaugurated in 1225. Around the year 1350 the church was enlarged and converted into a basilica. The two-storey magazine was also added then above the nave as a warehouse for merchants.
Following the Reformation, the church was transformed into a parish church for the town of Visby. All other churches were abandoned. Shortly after the Reformation, in 1572, Gotland was made into its own Diocese, and the church designated its cathedral.
There is not much left of the original interior. The font is made of local red marble in the 13th century. The pulpit was made in Lübeck in 1684. There are 400 graves under the church floor.