River Monnow in the context of "Monmouth"

Blestium (also Blestio in the Antonine Itinerary (Iter XIII)) was a small fort and iron working centre in the Roman province of Britannia Superior, part of Roman Britain. It has been identified with the site of the later town of Monmouth in south east Wales, located adjoining the confluence of the River Monnow with the River Wye. A plaque on the local bank records its position.

Monmouth Castle (Welsh: Castell Trefynwy) is a castle close to the centre of the town of Monmouth, the county town of Monmouthshire, on a hill above the River Monnow in south-east Wales.

Once an important border castle, and birthplace of Henry V of England, it stood until the English Civil War when it was damaged and changed hands three times before being slighted to prevent it being fortified again. After partial collapse in 1647, the site was reused and built over by Great Castle House, which became the headquarters and regimental museum of the Royal Monmouthshire Royal Engineers.

Monnow Bridge (Welsh: Pont Trefynwy Welsh pronunciation: [pɔnt tre:vənʊɨ]), in Monmouth, Wales, is the only remaining fortified river bridge in Great Britain with its gate tower standing on the bridge. Such bridge towers were common across Europe from medieval times, but many were destroyed due to urban expansion, diminishing defensive requirements and the increasing demands of traffic and trade. The historical and architectural importance of the bridge and its rarity are reflected in its status as a scheduled monument and a Grade I listed building. The bridge crosses the River Monnow (Afon Mynwy) 500 metres (1,600 ft) above its confluence with the River Wye.

Monmouth had been a significant border settlement since the Roman occupation of Britain, when it was the site of the fort of Blestium. The River Wye may have been bridged at this time but the Monnow, being easily fordable, appears not to have had a crossing until after the Norman Conquest. According to the local tradition, construction of Monnow Bridge began in 1272 to replace a 12th-century Norman timber bridge. Through the medieval era, the English Civil War, and the Chartist uprising, the bridge played a significant, if ineffectual, role in defending Monmouth. It also served as a gaol, a munitions store, a lodge, an advertising hoarding, a focus for celebrations and, most significantly, as a toll gate. Much of the medieval development of Monmouth was funded by the taxes and tolls the borough was entitled to raise through royal charter. The tolls were collected through control of the points of entry to the town, including the gatehouse on Monnow Bridge.