San Esteban de Deyo, also called the Castillo de Monjardín, is a ruined castle on a hill overlooking Villamayor de Monjardín in Navarre. The castle lies at an elevation of 890 metres. The castle has a Roman foundation, but was repeatedly rebuilt over the centuries. It was one of the last fortresses of the Banu Qasi, the local Muslim dynasty, before it was taken by King Sancho I of Navarre in 914. According to the Historia Caroli Magni et Rotholandi, the castle was actually taken by Charlemagne from a Navarrese prince named Furré. Only the walls of the castle stand today. Many of the stones were taken to build a Baroque hermitage, the Ermita de San Esteban, in the 17th century.
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.