Monmouth Castle

Monmouth Castle stands above the River Monnow in the centre of Monmouth, a town in Monmouthshire. Built soon after the Norman Conquest by William FitzOsbern, it began as an earth and timber ringwork and later gained stone walls before 1150. The castle overlooks the meeting of the Monnow and Wye rivers, a strategic spot chosen by Norman lords to guard the Welsh border. For centuries it served as a Marcher stronghold, ruled by local lords who answered directly to the king. Henry IV made it his residence, and his son Henry V was born here in 1386. The castle also briefly held Edward II as a prisoner before his transfer to Berkeley. The castle’s history reflects the turbulent centuries of the Welsh Marches. After passing through the hands of Simon de Montfort and Edmund Crouchback, it was improved with decorated windows and a new roof in the early 14th century. During the Owain Glyndŵr rebellion, nearby towns were attacked but Monmouth remained a secure stronghold. By the 16th century, its outer bailey had become Agincourt Square, a busy market place. The Great Hall hosted the county’s Courts of Assize when Monmouth became the county town. Today only parts of the Great Tower and Hall remain above ground, surrounded by later buildings. Great Castle House, built in 1673 on the site of the old round tower, now serves as the headquarters of the Royal Monmouthshire Royal Engineers. Their museum in the stable block tells the regiment’s story from 1539 to the present. The castle ruins and Great Castle House are Grade I listed, cared for by Cadw. Visitors can walk among the remaining walls and towers while Agincourt Square still forms the heart of the town below.