Castle Coole (from Irish: Cúl[1]) is a townland and a late-18th-century neo-classical mansion situated in Enniskillen, County Fermanagh, Northern Ireland.

The townland, which is 529 acres (214 ha) in size,[2] is situated in the civil parish of Derryvullan, in the historic barony of Tirkennedy,[2] as well as Fermanagh and Omagh district.

The site of a 17th-century house and bawn and formal garden at Castle Coole (grid ref: H2574 4333) are Scheduled Historic Monuments.

Lord Belmore was the Member of Parliament for County Tyrone in the former Irish House of Commons in Dublin and a wealthy heir to 70,000 acres (28,000 ha) of land throughout Ireland, acquired by ancestors with a successful background in merchantry.

The income generated by the estates allowed Castle Coole to be constructed at a cost of £57,000 in 1798, equivalent to approximately £20 million today.

Between 1980 and 1988, the mansion was closed to the public while the National Trust undertook major restoration work, including the dismantling the façade to replace metal anchors that hold the stone in place as these were corroding.

As part of the transfer of ownership to the National Trust there is an agreement that the Earl Belmore retains an apartment in the S wing, currently used by his heir and family.

Wyatt adhered closely to the Neo-classical ideal of restraint, symmetry and meticulous proportions, with architectural features carefully scaled.

[citation needed] Notable aspects of the mansion include the Portland stone façades and sober portico with Ionic capitals.

Other furniture was placed by the second Earl, when the Regency style was in vogue and by later generations, so that the interior appearance today is many layered, not just neo-classical.

This below-ground area is partially restored and open to the public and contains kitchens, servants' hall, larders, wine-cellars, laundry, a Roman style plunge-bath, a brewery and other offices.

Externally, the practical offices supporting the house are all accessed by a long inclined tunnel from the stable yard 260 feet (80 m) away, so that tradesmen, servants and estate staff approached and left the house unseen, with the architect's Neo-classical ideal composition above ground left seemingly undisturbed by day-to-day business.

Numerous out-buildings can be found on the estate; those of interest include lodges, "Grand Yard", workshops, stables, and a "Tallow House" (originally used for candle-making, now a gift shop and reception area).

Much of the native oak, ash and beech planting of the landscape park remains, today grazed by cattle and sheep as originally intended.

A 'ha-ha' – that is a ditch to control livestock movements without visual interruption to the landscape resulting from a fence or a wall – can be found near the mansion.