Tinboeth Castle is believed to have been built by Roger Mortimer during the 13th century. Following Mortimer's death, the castle fell into ruin and little of the structure remains. The castle was constructed in an Iron Age hillfort and measures around 100 metres in diameter. The Royal Commission on the Ancient and Historical Monuments of Wales notes that the remains indicate the site featured a twin-towered gatehouse on the north-east corner of the structure.
The outer bailey of the castle utilised the hillfort as a defence, while the inner bailey featured a stone wall which was accessed by the gatehouse.
An earthwork remains, believed to be the remains of a wall, but little stonework above ground except the collapsed remains of the gatehouse.
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.