The branch line from the
Great Northern Railway's (GNR) station at
Highgate to
Alexandra Palace was built by the
Muswell Hill Railway (MHR) and opened on 24 May 1873. Cranley Gardens station opened on 2 August 1902. In 1911, the line was taken over by the GNR. After the
Railways Act 1921 created the
Big Four railway companies, the line became part of the
London & North Eastern Railway (LNER) from 1923, which closed the station on 1 December 1930 and reopened it in July 1932. In 1935, the
London Passenger Transport Board (LPTB) planned, as part of its
Northern Heights plan to take over the line from LNER, together with its routes from to and . The line was to be modernised to use electric trains and amalgamated with the Northern line. At Finsbury Park, the line was to be connected to the Northern line's
City branch, so that services from Cranley Gardens would have continued to . Works to modernise the track began in the late 1930s and were well advanced when they were halted by the Second World War. Works were completed from Highgate to High Barnet and and that section was incorporated into the Northern line. Works on the tracks between Finsbury Park and Alexandra Palace were halted and the LNER continued to be operate the line. In 1942, LNER services through Cranley Gardens were reduced to rush hour only operations. After the war, no work was carried out as maintenance works and reconstruction of war damage on the existing network had the greatest call on LPTB funds. Funds for new works were severely limited and priority was given to the completion of the western and eastern extensions of the
Central line to , and . Despite being shown as under construction on underground maps as late as 1950, work never restarted on the unimplemented parts of the Northern Heights plan.
British Railways (the successor to the LNER) closed the line temporarily from 29 October 1951 until 7 January 1952, before the last passenger services ran between Finsbury Park and Alexandra Palace on 3 July 1954. The line continued to be used for goods services until 18 May 1957, when it was closed completely. The track was subsequently removed and the buildings were demolished. {{Adjacent stations|noclear=y ==The site today==