The halt on Bushey Mill Lane was opened in 1910 and called Callowland Halt, but in 1927 it was renamed Watford North Station.
Around 1938-39 the Watford By-Pass was constructed and various factories appeared, which required sidings, between the By-Pass and Bushey Mill Lane.
In later years the main use of the sidings on the west of the branch line between the By-Pass and Bushey Mill Lane was as a coal concentration depot.
Ordnance Survey Map 1939
