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The station opened in 1870 as "Barnsbury" replacing the 1852 Caledonian Road station which was slightly west of the present site. Barnsbury was renamed "Caledonian Road & Barnsbury" in 1893.
Between 14 May 1979 and 11 May 1985 the station was served by the Crosstown Linkline diesel multiple unit service between Camden Road and North Woolwich.
To allow four-car trains to run on the London Overground network, the North London line between Gospel Oak and Stratford closed in February 2010, and reopened 1 June that year, in order for a new signalling system to be installed and 30 platforms to be extended. After the reopening the work continued until May 2011 with a reduced service and none on Sundays.
Design
The station entrance on Offord Street leads to the old westbound platform (until February 2010) from which a footbridge gives access to the newer island platforms, numbered 2 and 3, probably to distinguish them from the old platform 1. There is a footpath, with Oyster readers, from Caledonian Road to the entrance.