Townley Hall, Townleyhall, Co. Louth

The effect, achieved through cantilevering, in which each stone step is anchored only at one end into the wall and left to project outward, is the kind of engineering that architects of the period liked to disguise as simplicity. Here it is put on full display, lit from above, and paved beneath in Portland limestone cut into geometric patterns.

The house was built around 1800 for Blayney Townley Balfour, and its design is credited to Francis Johnston, an architect whose broader body of work includes some of Ireland's most recognisable public buildings, but who is thought by many to have done his finest work here. Balfour's own travels around Europe are said to have shaped the design, and the result is a rigorously Greek Revival composition: a tetrastyle portico (a porch fronted by four columns) in the Doric order faces east, its fluted columns and entablature (the horizontal band of stonework it carries) echoed in the denticulated cornice, a row of small tooth-like blocks, that runs along the tops of the walls. The stonework throughout is tooled limestone ashlar, precisely cut and finished, sitting on a limestone plinth with matching string courses marking the floor levels. Even the doors received the same attention: mahogany imported from Cuba, panelled and fitted with care that matches the more obviously showpiece rotunda.

Externally the house presents as a seven-bay, two-storey block over a basement, with an attic level tucked beneath a hipped slate roof, and a single-storey service wing extending to the west. A round pond lies to the east, and the ground falls away in lawns to the south, giving the house the elevated, surveying position typical of country houses of its era. To the north-west stands a complex of outbuildings, the working buildings, and behind the west wing's Doric-columned doorways lie blocked openings, small architectural puzzles left for anyone who looks closely enough at how the service quarters were once organised.