The B681 was a C-shaped road in Nottingham city centre, acting as a western bypass.
It originally started on the A52 Carrington Street and headed west along Canal Street and Castle Boulevard into Lenton. It then turned north to get to Radford (crossing the A52 again en route) before heading east to its terminus on the A60 Mansfield Road.
The southern section was taken over as part of an extension of the A453 around 1935 whilst the remainder lasted until at least the 1960s before also gaining Class I status.
The section that was the A453 is now part of the A6005; the remainder is the A6130.