The B5406 number was allocated to a section of Watling Street in Telford, Shropshire that has a confusing numbering history.
Oakengates in 1922, showing A5 and B5060 over what would become B5406
In the original 1922 listings, the B5060 number was allocated a small part of Watling Street in eastern Shropshire between Oakengates and Ketley, via Oakengates Town Centre, and finally up a rather steep hill into St. George's. Presumably due to this steep hill, most traffic avoided this small section of Watling Street and instead diverted via the Holyhead Road before turning northwards along Furnace Road and Stafford Street before rejoining Watling Street in the centre of St. George's. This busier route, therefore, became the A5, whilst the original line of Watling Street was considered sufficiently busy to become B5060.
By the time of publication of the relevant 1926-27 MoT Map, it was realised that the route north of St. George's to Donnington via Gower Street, St. George's Road and Wrekin Drive was sufficiently busy to be upgraded to a B-class road, and so B5060 was extended over this route. This meant that A5 and B5060 met at a cannon, and that B5060 became an L-shaped route rather than an east-west route.
The now-unclassified former B5406 Station Hill
In 1932, the St. George's Bypass along what is now Snedshill Way and the carefully named "St. George's Bypass" opened to the east of the village. The A5 was therefore rerouted along the bypass, meeting the then-A41Holyhead Road slightly to the east of its former location. The old route of the A5 through the centre of St. Georges then required a B-class number. Presumably in order to simplify the route numbering in the area, it was decided to allocate different numbers to the north-south route and east-west route that met in the centre of St. George's. Oddly, the B5060 number was allocated to the north-south route, whilst the east-west route gained the B5406 number. This meant that none of the original B5060 was part of the post-1932 route.
Today, the B5406 route is unclassified and partially pedestrianised through Oakengates Town Centre.