Former Coachhouse at Gwydir Castle including associated wall and entrance arch adjoining to the E

The former coachhouse at Gwydir Castle, along with its associated wall and entrance arch to the east, is a notable structure built from rubble. It features large clasping buttresses at the corners and consists of two sections. The left section is a two-storey square block that served as a stable and living area, while the coachhouse section extends as a single-storey projection. The left section has a parapet and a moulded cornice, topped with a flat roof.

On the north side, facing the garden, there is a central entrance with a Tudor arch and chamfered reveals, which is slightly elevated on a raised terrace. Flanking this entrance are leaded windows. To the right, there is a smaller but similar entrance, both of which have ribbed and studded doors; the smaller door features a contemporary glazed panel from the 1820s. The chamfered arch and reveals are made of slatestone, possibly re-used material from the early 16th century, incorporated after the demolition of subsidiary ranges at the castle in 1816. The upper floor has two chamfered slit-lights beside a modern leaded window, which is an enlargement of a similar light. There are additional slit-lights on the east and south sides, with two and three respectively. The coachhouse section has a slate roof with a parapet and cornice, which continues to form a shallow gable on the west side. A large former coach/cart opening features a depressed slatestone arch, now with modern infill and a window, along with another plain leaded window on the north face. The front of the gable entrance has a fragmentary cobbled pavement, and the interiors are plain and modern.

At the rear of the building, extending eastward for about 50 meters and running parallel to the road towards the castle, is a section of rubble perimeter wall approximately 1.8 meters high, capped with large dressed slatestone. This wall is topped with three decorative slatestone trefoil finials typical of the Gwydir style. The wall then returns to the northwest in a zigzag in front of the west wing of the castle, where there is a service entrance with a boarded and studded door, topped with a finial and a raised flat arch above.