DisgrifiadViaduct described by Willaim Coxe in his Tour through Monmouthshire. Illustrated by Sir Richard Colt-Hoare from original drawings probably made in 1796 which show the arches blocked in to provide workers housing as described by Coxe. Viaduct buried by mining activity in the nineteenth century, but probable location established from historic maps created between 1810 and 1823. Excavation of probable site by the Time Team television programme confirmed its location and survival.