Wharncliffe Viaduct, Hanwell, London
The Wharncliffe Viaduct (also known as Hanwell Viaduct) was designed by I K Brunel and completed in 1837. 300 yards long, it carried the two broad guage (7 foot wide) tracks of the new Great Western Railway over the valley of the River Brent. Sections of the GWR have been nominated for World Heritage Site status.