Its original owner had it constructed so he could watch his horses being put through their paces on the ground below. A belvedere, as such structures are known, is essentially a raised platform or room designed to command a view, and this one was purpose-built for equine spectating rather than landscape appreciation in any conventional sense.

Edward O'Brien had the building constructed around 1740, to a design by the architect John Aheron. The structure is a freestanding, octagonal, double-height belvedere raised over a part-basement, and it is considerably more elaborate than its function might suggest. The roof is cut limestone, finished with a moulded cornice and blocked course, and capped with an obelisk at the apex. Inside, the basement is groin-vaulted in yellow brick, while the main chamber above features cross-ribbed brick vaulting and retains a chimney flue, which implies the building was intended for genuine occupation and comfort during those watching sessions. The exterior walls are roughcast render over rubble stone, with cut-stone string courses and red brick dressings around the openings. The whole structure sits on a star-shaped platform formed by four triangular mounds, approached by a flight of cut-stone steps. The Irish Georgian Society undertook a restoration of the building in 1998, addressing the stonework, windows, and roofing, and fitting steel support bands around the structure to stabilise it.