Castle Howard in County Wicklow is built in two distinct styles simultaneously, part Romantic Castle and part Abbey, a combination that gives it an unusual, slightly theatrical presence on its hilltop site overlooking the Meeting of the Waters, the confluence of the Avonmore and Avonbeg rivers made famous by Thomas Moore's poem. The castle section rises with three-stage towers and battlemented parapets, while the abbey section beside it settles into two storeys of gothic tracery windows beneath its own battlemented parapet. A large conservatory projects from the south-east side, and the front door, a timber studded and sheeted affair set within an ogee-shaped opening, carries a reeded stone surround and a blind fanlight treated with matching sheeting. The whole is finished in render with stone dressings, and the window openings are generally flat-headed with gothic tracery and drip mouldings to channel rainwater clear of the frames.

The house was built in 1811 for Lieutenant-Colonel Robert Howard, and was designed by Sir Richard Morrison, one of the most prolific architects working in Ireland during the late Georgian and Regency periods, responsible for country houses across several counties. Morrison here wrapped the new building around the fabric of an earlier house, so there is older material embedded within the present structure. The setting was carefully considered: the house sits within a large wooded demesne, with manicured gardens close to the building, a small lake and boathouse, and a tall folly positioned beside a walled garden. The folly, a purely decorative or atmospheric structure with no functional purpose, is a characteristic touch of the Romantic period, when landowners frequently commissioned such features to lend their estates an air of antiquity or melancholy.