The Wharncliffe Viaduct is a brick-built

viaduct A viaduct is a specific type of bridge that consists of a series of arches, piers or columns supporting a long elevated railway or road. Typically a viaduct connects two points of roughly equal elevation, allowing direct overpass across a wide v ...

that carries the

Great Western Main Line The Great Western Main Line (GWML) is a main line railway in England that runs westwards from London Paddington to . It connects to other main lines such as those from Reading to Penzance and Swindon to Swansea. Opened in 1841, it was the or ...

railway across the Brent Valley, between

Hanwell Hanwell () is a town in the London Borough of Ealing, in the historic County of Middlesex, England. It is about 1.5 miles west of Ealing Broadway and had a population of 28,768 as of 2011. It is the westernmost location of the London post t ...

and

Southall Southall () is a large suburban county of West London, England, part of the London Borough of Ealing and is one of its seven major towns. It is situated west of Charing Cross and had a population of 69,857 as of 2011. It is generally divided ...

Ealing Ealing () is a district in West London, England, west of Charing Cross in the London Borough of Ealing. Ealing is the administrative centre of the borough and is identified as a major metropolitan centre in the London Plan. Ealing was histor ...

, UK, at an elevation of . The viaduct, built in 1836–7, was constructed for the opening of the

Great Western Railway The Great Western Railway (GWR) was a British railway company that linked London with the southwest, west and West Midlands of England and most of Wales. It was founded in 1833, received its enabling Act of Parliament on 31 August 1835 and ran ...

(GWR). It is situated between

and

stations, the latter station being only a very short distance away to the east. The viaduct was the first major structural design by

Isambard Kingdom Brunel Isambard Kingdom Brunel (; 9 April 1806 – 15 September 1859) was a British civil engineer who is considered "one of the most ingenious and prolific figures in engineering history," "one of the 19th-century engineering giants," and "one ...

, the first building contract to be let on the GWR project, and the first major engineering work to be completed. It was also the first railway viaduct to be built with hollow piers, a feature much appreciated by a colony of

bat Bats are mammals of the order Chiroptera.''cheir'', "hand" and πτερόν''pteron'', "wing". With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most ...

s which has since taken up residence within.

Design

Constructed of

engineering brick Engineering bricks are a type of brick used where strength, low water porosity or acid (flue gas) resistance are needed. Engineering bricks can be used for damp-proof courses. Clay engineering bricks are defined in ''§ 6.4.51'' of ''British Sta ...

, the viaduct has eight semi-elliptical arches, each spanning and rising . It is wide. The supporting piers are hollow and tapered, rising to projecting stone cornices that held up the arch

centring Centring, centre, centering"Centering 2, Centring 2" def. 1. Whitney, William Dwight, and Benjamin E. Smith. ''The Century dictionary and cyclopedia''. vol. 2. New York: Century Co., 1901. p. 885., or center is a type of formwork: the temporary str ...

during construction.