Carlow Castle

Carlow Castle is located near to the River Barrow in County Carlow, Ireland. It was built between 1207 and 1213, and is a National Monument of Ireland.
The earliest written record of this castle is from 1231 but it does not name its builder. It is widely assumed that the castle was built by William Marshal the elder in the time period between 1207 and 1213 which he spent in Ireland. The castle in Carlow was the very first of its kind in Ireland, a towered keep, where a huge rectangular tower is surrounded by four smaller three-quarter-circular towers at the corners of the rectangle. However, there have been doubts that the castle in Carlow supported the traditional function of a keep, i.e. to serve as a refuge of last resort. Instead it deliberately diverted from the contemporary standard in England and continental Europe, i.e. there is no towered curtain, no gate house, and no undivided great hall. Similar castles of the same period were erected in Ferns, Lea, and Terryglass.

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