This article is about the original B4504 in Hertfordshire.
For the current B4504 in Redditch, see B4504
The pedestrianised section of Vicarage Road, formerly the B4504
The B4504 was inaugurated in the early 1930s as a second classified road between Rickmansworth and Watford, running parallel to the A412 for its entire length.
The road started on the A404 at Batchworth, to the east of Rickmansworth, and headed eastwards via a winding route to end on the A411 (formerly A41) Watford High Street.
In the 1970s the entire road was upgraded to Class I status, becoming the A4145. A short section to the west of Watford town centre has since been pedestrianised and the eastern end of the road was unclassified at the same time as Watford High Street.