Chislehurst Junction

Chislehurst Junction is an important railway junction near Chislehurst in the London Borough of Bromley, England. It is the point where the South Eastern Main Line and the Chatham Main Line pass over each other, with diversion chords between each line. These are arranged such that a London-bound train on one line can transfer to the other, and likewise for services heading away from the capital.

The railways previously passed over each other without a junction, until the merger of the London, Chatham and Dover Railway (LCDR) and the South Eastern Railway (SER) on 1 January 1899 meant it made operational sense to build connections between the previously disparate networks. The first connection, the "down" Bickley Loop, opened on 8 September 1902 with a length of ¾ miles (1 km). The reverse connection opened six days later. These connecting loops allowed trains to/from London Victoria to operate on the former SER line. The west and east ends of the loops became known as Bickley Junction and Orpington Junction respectively, named after the next stations on the line at the time. The corresponding connection (the Chislehurst Loops), allowing transfer of Charing Cross trains to/from the Chatham line was, opened on 19 June 1904.

From 1925 the Southern Railway — which had been formed in 1923 assuming the junction's previous owners — began to electrify the routes through the junction. The first to be installed with a third rail was the Bickley Loop, on 12 July 1925. This was followed by full electrification between Orpington Junction and Charing Cross on 28 February 1926. In connection with this wave of electrification, a three-storey red brick substation was installed, immediately to the north of the Chatham line and west of the Charing Cross line.

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