B roads in Zone 1 of the Great Britain numbering scheme

B roads are numbered routes in Great Britain of lesser importance than A roads. See the article Great Britain road numbering scheme for the rationale behind the numbers allocated.

(In many ways this is 2 roads split: Queensbridge Road is fairly long, the others together form almost a continuous road albeit Warner Place is slightly east of Squirries Street, but there is a fair stretch of Hackney Road between the junctions of Warner Place and Queensbridge Road, with the latter further to the west. In addition Warner Place and Squirries Street are rather narrow minor-looking roads and their classification as part of a B-road seems only be to join the other two parts)

(The eastern end of this road is Butcher Row, which is a spur between the A13 and the A1203 and it is not clear what the classification of Butcher Row actually is. Some maps classify is also as B126 making it the only primary stretch of B-road. It is not possibly to drive along the length of the B126 as west of the junction of Brodlove Lane it is one-way West-only and east of that junction it is one-way East-only. Brodlove Lane itself is unclassified.

Prescot Street is also shown on google maps as part of the B126 but this seems to be a mis-classification. This road is also primary forming part of the inner-London ring road so that would mean the B126 would have primary status at both ends. According to Bing maps Prescot Street forms part of the A1210 which makes more sense).

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Wikipedia