Bridge, Alternan Park, Co. Sligo

This crossing over the Ballymeeny River in Alternan Park, County Sligo, sits in level wet pasture and was built without any walling along its edges, a detail that suggests it was never intended to carry carts or wagons. At one metre wide, it is more likely to have served people on foot, or perhaps livestock being moved across the river.

The bridge is built from roughly quarried limestone blocks set in a gravelly limestone mortar, with three slightly pointed arches spanning the river from south to north. Pointed arches, as opposed to the rounded semicircular form more typical of earlier medieval construction, allow weight to be distributed more efficiently, and they appear here in a modest, functional way rather than as any kind of decorative statement. The central arch is fractionally wider and taller than the two flanking it, measuring 1.5 metres in height and 1.45 metres across, while the side arches come in at 1.3 metres high and 1.25 metres wide. The voussoirs, the wedge-shaped stones that form the curve of each arch, are left undressed and blend without distinction into the rest of the stonework, giving the whole structure a plain, unadorned character. On the southern side, the piers were originally fitted with triangular breakwaters, low projecting points of masonry designed to deflect the force of the current and reduce pressure on the columns during high water, though these are now partly ruined.