From the Wikipedia page 
Staines High Street railway station formerly served the town of Staines-upon-Thames, on the Windsor & Eton line of the London and South Western Railway. It was opened on 1 July 1884 and closed on 1 February 1916 and was built for trains using the West Curve. When passenger services no longer ran via that chord, it became redundant however it remained in use for freight traffic until the mid 1960s after which the embankment was removed. A multi-level car park stands on the site of the chord. There is no remains of the station.
Under the Heathrow Airtrack rail link plan the West Curve would be reinstated, but the proposal to have a station near the site of this former one has been dropped.