The remains

The ruins of Newport castle.
Newport Castle (Welsh: Castell Casnewydd) is a ruined castle in Newport, Wales. It was built in the 14th century, probably by Hugh de Audley, 1st Earl of Gloucester or his son-in-law, Ralph, Earl of Stafford, with the purpose of managing the crossing of the River Usk. The castle was used as administrative offices for the collection of rent and dues from local tenants, and was also a residence and a garrison. In 1402 it was sacked by Owain Glyndŵr. It was in disrepair by 1522, and was taken by Oliver Cromwell's forces during the Civil War. Its use declined further in later centuries. It has been a Grade II* Listed building since 1951.
The castle was built of Old Red Sandstone and local grey limestone. Originally, it was surrounded by a moat, within a "rectangular walled court". Trett said that "in its heyday it would have dominated the town and the river crossing." It had three tall towers, a large rectangular central tower and two two-storey polygonal end towers, which connected by straight walls. Its form is based upon the line of the river bank on which it is located. A vaulted audience chamber sat above a watergate "a fortified gate... for use of people and supplies arriving by boat". Above the watergate were turrets.

Within the castle were a great hall, kitchen, a gallery, chambers and, after the 15th century works by Humphrey Stafford, "a series of luxurious" apartments, those used by the lord being in the south tower. Architectural historian John Newman states that the most remarkable feature is the T-shaped room in the central tower above the watergate, which "must have provided a remarkable ceremonial setting."