Wharncliffe Viaduct
The Wharncliffe Viaduct is a brick-built viaduct that carries the Great Western Main Line railway across the Brent Valley, between Hanwell and Southall, Ealing, UK, at an elevation of 20 metres (66 ft). The viaduct, built in 1836–7, was constructed for the opening of the Great Western Railway (GWR). It is situated between Southall and Hanwell stations, the latter station being only a very short distance away to the east.

The Wharncliffe Viaduct is a brick-built viaduct that carries the Great Western Main Line railway across the Brent Valley, between Hanwell and Southall, Ealing, UK, at an elevation of 20 metres (66 ft). The viaduct, built in 1836–7, was constructed for the opening of the Great Western Railway (GWR). It is situated between Southall and Hanwell stations, the latter station being only a very short distance away to the east.
Check the official site before travelling; hours and prices can change.
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Source: wiki-list