Work on extension of LO’s East London line to Clapham Junction underway May 20, 2011 | Europe News Transport for London’s (TfL) contractor Birse Metro has started construction of track to extend London Overground’s (LO) East London line to Clapham Junction. The 1∙3 km track is being bui... This content is available to only subscribers. Username or E-mail Password Remember Me Forgot Password