Set on Castle Street, between the French Tower and the Watch Tower, the Double Tower remains well preserved as one of the 17 towers which were part of the city walls of Waterford city. It was built in the latter part of the 15th century and the early part of the 16th century. Six of the original 17 towers survive to this day; the other five being Reginald's Tower, Beach Tower, Semi-Lunar Tower, French Tower, and Watch Tower (Waterford).

Layout

The name Double Tower probably originates from the fact that there are two chambers inside it. One chamber contains a passageway which leads to the Benedictine Priory; the other, bigger chamber used to contain a flight of stairs leading to the upper floors and battlements. The Benedictine Priory was the priory of St. John and was owned by the Benedictine priory of St. Peter and Paul of Bath in England. Along with the citizens of Waterford, this priory funded the construction of the towers and walls in this part of the city.

The Double Tower is oblong in plan, measuring 7m in length in the northwest-southeast direction, and 4.5m in width_. Its height_ is 10.5m. It looks like mini-tower house, joined at either end by the city wall. However, habitation was not the primary function of this building. The city wall at either end abuts onto the exterior of the tower. This indicates that the tower was built earlier, and was originally a freestanding structure.