Glendun Viaduct, Irragh/Clegnagh Tls, Glendun, Co.Antrim

A triple-arched masonry road bridge of 1839 over the Dun River on the Cushendall - Ballycastle road. This bridge is constructed in sandstone throughout. Its abutments and piers are of sandstone blocks brought to courses, with plain quoins. Attached to the up- and downstream faces of the abutments and piers are shallow buttresses of randomly-size blocks which taper inwards on both their faces and edges as they rise. The buttresses are embellished with stepped, vee-jointed sandstone quoins, the faces of which are rusticated and margined. All the arches are of semicircular profile and have voussoirs detailed as the buttress quoins. The middle arch is the tallest and widest and spans the actual river. The flanking arches are of identical size: the N one spans a minor road along the left bank of Glendun whilst the S one is dry in normal circumstances. As none of the piers is footed in the river, no cutwaters were necessary. The arch soffits are of coursed sandstone blocks, with a row of projecting stones below arch spring level on which the falsework was set during their construction. Moulded sandstone string courses run through each arch at spring level and continue around the abutment and pier buttresses. The spandrels are of randomly-sized blocks brought to courses. A moulded sandstone string course runs across each face at the base of the parapets. The parapets are of regularly-coursed rusticated and margined sandstone blocks with similarly detailed oversailing copings with sloping tops. The parapets terminate in out-projecting piers which are an upward continuation of the abutment buttresses. There are identical out-projections along the outside faces of the parapets at the top of each pier buttresses. The approach walls are of random rubble. A substantial earthen embankment carries the road across to the S end of the bridge. Setting: The bridge and road span the deep valley carved out by the Dun River and are surrounded to all sides by fields and patches of woodland.