London is set for a new 700 million Overground line
The West London Orbital would create a new London Overground branch linking Hounslow to Hendon and West Hampstead via Old Oak Common, costing about £700m.
The Elizabeth line that never was: The Watford Junction extension from Old Oak Common
Old Oak Common could have been configured to extend Elizabeth line services northwest toward Watford Junction via sidings linkage to the WCML, offering diversion capacity.