The first section was opened by the Eastern Counties Railway (ECR) on 20 June 1839 from the London end at Devonshire Street to Romford, extended on 1 July 1840 to Bishopsgate (London end) and Brentwood.
Another branch, the Chingford branch line, went from Lea Bridge to Walthamstow, Shern Hall Street, in 1870, extended southwards to Hackney Downs in 1872 and northwards to Chingford in 1873.