|Length:||1.4 miles (2.3 km)|
|Met (1923):||A11, B125, A13, A102|
|Now part of:||A12|
|Route outline (key)|
The B122 was upgraded to Class I status in the 1930s, presumably becoming a northern extension of the A102. Then it was upgraded further in the 1970s with the building of the East Cross Route. The A102(M) East Cross Route was cut through south from the Hackney Marshes and took over the route of the ex-B122 en route to cross the River Thames. Part of the ex-B122 is still in situ, for example St Leonard's Street in Bow, but the majority was destroyed when the motorway was built.
In 2000 the motorway was downgraded and the road is now the southern end of the A12.