The city of Soria formed in a valley near the castle that defended the Douro Riverbanks on the border between the Crowns of Aragon and Castile. The city was destroyed towards the end of the 12th century when Sancho of Navarre attacked it, therefore a great defensive wall was built to prevent further destruction. The wall defended a surface of 100 hectares that went from the Douro River up to the pastureland known as “La Dehesa”, and also from the castle up to the hill where you can find the Chapel of El Mirón.
The Sorian wall was destroyed by General Durán at the end of the Spanish Independence War to avoid French troops from entrenching in the castle. This is the reason why there are so few remains of this castle and why we can only see part of the tower and some parts of the defensive walls. From the castle, you can see a 360º view of the city and the bridge that crosses the Douro River, and in the Chapel of San Saturio, you can see frescos depicting the castle as it once was.
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.