Craigmore Viaduct Craigmore Viaduct The Craigmore Viaduct () is a railway bridge near Bessbrook, County Armagh, Northern Ireland, known locally as the 18 Arches. (OS Grid ref: Jo628). Near Newry railway station. The bridge was designed by John Benjamin Macneill, an eminent Irish civil engineer, with construction beginning in 1849 for the Dublin and Belfast Junction Railway. The bridge was formally opened in 1852. It spans the valley of Camlough River. The viaduct consists of 18 arches of 60 ft span, the highest being 126 ft, making Craigmore the tallest viaduct in Ireland. It is around a quarter of a mile long
Millau Viaduct sheath). The exterior envelope of the stays is itself coated along its entire length with a double helical weatherstrip. The idea is to avoid running water which, in high winds, could cause vibration in the stays and compromise the stability of the viaduct. The stays were installed by the Freyssinet company. To allow for deformations of the metal road deck under traffic, a special surface of modified bitumen was installed by research teams from . The surface is somewhat flexible to adapt to deformations in the steel deck without cracking, but it must nevertheless have sufficient strength to withstand motorway