Glashagh Bridge No 1, Ganvaughan Road, Castlederg, Co Tyrone, BT81 7SY

This is a single-span road bridge, built approximately between 1840 and 1859, carrying Ganvaughan Road over Killen Burn. The bridge is of attractive design, possessing good proportions and detailing, especially in its ornate dressings of contrasting stonework. The bridge's setting is rural and unspoiled, contributing positively to the local landscape and having an industrial archaeological interest.

The abutments, spandrels, and parapets are constructed from roughly coursed rubble, with a string-course of dressed rockfaced sandstone running to carriageway level. The parapet is finished with rounded dressed rockfaced sandstone coping. A single segmental-headed arch, featuring dressed rockfaced voussoirs, provides the bridge's span; the arch soffits are rendered with cement. The carriageway is approximately 5 metres wide. The parapet wall extends beyond the abutments to rounded ends, and a timber stile is located to the northeast. The bridge is situated on a rural road west of Castlederg village, where Killen Burn flows into the River Derg. The riverbanks are bounded by wire fencing and hedging.

An earlier, uncaptioned bridge is shown on an Ordnance Survey map from 1833 spanning Killen Burn, on the road between Castlederg and Fermanagh. The present bridge's more sophisticated stonework and ornamentation indicate a construction date in the mid-nineteenth century. The bridge was named 'Glashagh Br' on an 1853 Ordnance Survey edition, and by 1905, an additional bridge was depicted over the River Derg nearby.