Digswell Viaduct

Digswell Viaduct is a railway structure in Welwyn with a distinctive red brick construction that stretches 475 meters across the Mimram Valley, supported by 40 arches that rise 30 meters above ground. The structure narrows from four tracks to two and forms a connection between Welwyn Garden City and Welwyn North stations.

Engineer Lewis Cubitt designed the viaduct in 1848, with construction completed by 1850 using around one million tons of earth to shape the landscape. The structure became part of the East Coast Main Line and represented a major engineering feat for its time.

The structure displays typical Victorian craftsmanship with its distinctive red brick and arches that become immediately recognizable as trains pass through the Mimram Valley. Visitors can observe the engineering skill in the stonework details and curved structure when viewing it from below.

The structure is best viewed from a distance below or from nearby paths that run along the Mimram Valley. It remains an active railway line, so visitors should stay clear of the tracks and view it from outside the safety perimeter.

Queen Victoria refused to cross the viaduct at its 1850 inauguration, choosing instead to travel by horse-drawn carriage through the valley. This rejection by the monarch was surprising for a structure meant to showcase technological progress.