The Brentford branch line, also known as the Brentford Dock Line, is a freight-only branch railway line in west London, England. The route, which opened in 1859, was backed by the Great Western Railway and built by the Great Western & Brentford Railway Company. It ran 4 mi (6.4 km) from Southall to Brentford Dock. In 1964, the line to the wharves was closed. The branch now runs from the Great Western Main Line to a goods yard and waste transfer station in Brentford.