The railway line between Chatham and Faversham was opened on 25 January 1858 by the East Kent Railway Company, which became the London, Chatham and Dover Railway (LCDR) the following year. The station at Newington was opened by the LCDR on 1 August 1862.
The station is 41 miles 42 chains (66.8 km) from London Victoria (measured via Herne Hill). Most of the line between Swanley and Dover has two tracks, but there are four tracks from a point about half a mile east of Rainham to 41 miles 52 chains (67.0 km), at the eastern end of Newington station. The outermost two tracks are designated the "loop" lines, and the innermost two are the "main" lines. At Newington, there are two platforms, one on each of the "loop" lines; these are capable of accepting 12 car trains.
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