|Location Map ( geo)|
|From:||Marylebone Road (TQ287822)|
|To:||Russell Square (TQ299819)|
|Distance:||1.2 miles (1.9 km)|
|Meets:||A4201, A501, A4201, A5204, A400, A4200|
|Old route now:||A5204, A4200|
|Route outline (key)|
The B506 is a complicated B-road in central London. Its present route consists of two unconnected sections but none of this is the road's original route.
Great Portland Street
The road starts at a gyratory on the A501 and A4201 by Great Portland Street tube station. The road then heads south along the one-way Great Portland Street. There is no corresponding route for northbound traffic.
The B506 becomes two-way at the junction with Gildea Street and continues on to where this section ends at traffic lights on the A5204 Mortimer Street. The remainder of Great Portland Street, ahead, is apparently part of the A4201 despite the fact that the mainline of that road follows the parallel Regent Street.
In the 1922 Road Lists the B506 is described as London (Seymour Street, Wigmore Street, Goodge Street) - in other words it ran between the A5 Edgware Road and the A400 Tottenham Court Road parallel to the A40 Oxford Street. There was a short multiplex along the B505 at the western end of Mortimer Street.
The B505 was later upgraded to become the A4201 and the section of B506 west of this road was also upgraded to Class I status, probably becoming the A5204. Later still, the A4201 was moved westward from Great Portland Street into Portland Place and so the B506 was extended north along the vacated Great Portland Street. More recently, the A5204 was extended further along the remainder of the original B506, leaving the current route of the B-road with seemingly nothing in common with its original route.
The original section of the B506 was, however, later extended further east and when that became the A4201 this extension remained thus dividing the road into two sections. Following a multiplex south along the A400 Tottenham Court Road the B506 reappears heading east along Bayley Street. It then runs around three sides of Bedford Square (the fourth side to the east is the A400) then past the back of the British Museum to end on the A4200 Russell Square. The southern side of Russell Square was the B506 until the square was turned into a one-way gyratory and the whole thing taken over by the A4200; this number persists despite the fact it is no longer one-way.
The eastern section of the B506 cannot be followed in a vehicle as the entire road is one-way albeit not in the same direction - Montague Place, for example, takes traffic away from but not towards the British Museum.