The Liffey Viaduct or Liffey Railway Bridge is exclusively used by rail traffic and crosses the Liffey from a point west of the Heuston Train Station complex on the south side to a residential area on the north river bank. There is no pedestrian or road traffic access to the bridge, while trains approach the bridge from the only through platform at the station - number 10 - and from the north side through the Phoenix Park Tunnel.
Constructed between 1872 and 1877, the bridge is of wrought iron, a very typical bridge building material of the Industrial Revolution. The truss design, with the distinctive triangular lattice work pattern, is also a classic of the era.
Iron lattice girder bridges were introduced to Ireland and the U.K. by Irish railway engineer Sir John Benjamin Mc Neill, who was a pupil, and later an associate, of Thomas Telford. McNeill was also the engineer of the Dublin - Cork railway line which terminates at Heuston Station. On either side of the Liffey Viaduct there are approach spans of three masonry, semi circular arches built in stone. Seen from the ground, the bridge setting is strikingly sylvan notwithstanding its urban location: the river twists and turns gently below and trees frame the neat, box truss structure which is painted in muted shades to blend with the surrounding greenery.
The bridge was built to facilitate the interchange of rail traffic between three of the five Dublin railway termini at the time: Heuston, Broadstone and Amiens Street stations. Between them they catered for rail traffic from the south, the west, the midlands and the north. Today, the link is used mainly for rail freight, though the route is used for passenger trains on occasions when unusually large volumes of passengers are experienced, such as the days of All Ireland Finals.
A valuable part of Dublin’s industrial heritage, it is one of two railway bridges crossing the Liffey within the city, the other also known as the Liffey Viaduct but more familiarly as the Loopline Bridge. Older than the Loopline and even somewhat generic in nature, the bridge adds a certain charm and a definite eclecticism to Dublin’s Liffey bridge collection.