The Castello Svevo ('Swabian' or Hohenstaufen Castle) was originally built by the Saracens on the ruins of the ancient Rocca Brutia, around the year 1000. The castle was restored by Frederick II, Holy Roman Emperor, adding the octagonal tower to the original structure, in 1239. According to tradition, his son Henry lived in this castle, as a prisoner at his father's command. Louis III of Naples and Margaret of Savoy married in the castle and they both settled there in 1432.
All signs of the ancient Saracen structure have now disappeared. In the internal cloister, the modifications made by the Bourbons in order to convert it into a prison can also be seen. The entrance-hall is covered by ogival arches with engraved brackets. A wide corridor is dominated by some fleur-de-lis from the House of Anjou coat of arms. They are engraved on the ribbed Hohenstaufen arches.
References:The Broch of Clickimin is a large and well preserved, though somewhat restored broch near Lerwick. Originally built on an island in Clickimin Loch (now increased in size by silting and drainage), it was approached by a stone causeway. The water-level in the loch was reduced in 1874, leaving the broch high and dry. The broch is situated within a walled enclosure and, unusually for brochs, features a large 'blockhouse' between the opening in the enclosure and the broch itself. Another unusual feature is a stone slab featuring sculptured footprints, located in the causeway which approached the site. Situated across the loch is the Clickimin Leisure Centre.