The Bere Alston & Calstock Light Railway was authorised to redevelop a narrow gauge mineral line near Callington in south eastern Cornwall. This was served by a wharf at Calstock Quay on the river Tamar. The new railway was authorised to make connection with the Plymouth, Devonport & South Western Junction Railway at Bere Alston on the other side of the Tamar, for further transport by rail. The crossing was achieved by building this single track viaduct. With 12 x 60 ft. spans, a length of 333yds. and a height of some 120 ft. it is impressively slender and elegant. This is the largest viaduct in Britain to be constructed of concrete blocks. Designed by Galbraith & Church.