Llansteffan is located on the south coast of Wales, It was built by the Normans as part of their conquest of South Wales.
The site itself has been occupied since the Iron Age, since it provides commanding views of the Tywi estuary. Even today the original earthwork fortifications can still be seen, and they were incorporated into the defenses of the later Norman construction.
As it exists today, the castle is very much a ruin, consisting of a curtain wall and towers, all dating to the 12th and 13th centuries. After the Normans completed their conquest of Wales, it fell into ruin and by 1367 was what Wikipedia describes as “a poor state”.
I was excited to visit the castle because some of the people who fought over the castle, both Norman and Welsh, appear in my Gareth and Gwen Medieval mysteries. In the 1140s, the castle belonged to Maurice Fitzgerald, son of Gerald of Windsor (and builder of Carew Castle, among others). Maurice’s older brother, William was castellan of Pembroke Castle and both men served Gilbert de Clare, the Earl of Pembroke.
In 1146, the castle was captured by the Welsh King of Deheubarth, Cadell, and his brothers. Shortly afterwards, Cadell actually allied with Maurice and his brother–and the Clares–for a brief period when these Norman lords were in rebellion against King Stephen. These events are related in my book, The Worthy Soldier.
This alliance didn’t last, particularly after the crowning of Henry II, after which the Normans took Llanstephan back. The castle was captured in the 13th century by both Llywelyn Fawr and his grandson, Llywelyn ap Gruffydd, both of whom were Princes of Wales, but each time the castle was ultimately returned to Norman control.