The B285 is a short B-road running south of Wimbledon. The road was originally unclassified but the number had come into existence by the mid-1920s as the northern half of the current route (north of the A238). The remainder of the road was classified soon afterwards.
The road starts on the A219 one-way loop in the centre of Wimbledon. It heads south along the residential Hartfield Road and soon reaches traffic lights on the A238. The road turns right and multiplexes along that road across a level crossing over the Tramlink (presumably controlled by the same set of lights), then regains its number by turning left onto Dorset Road. We continue through the suburbs and it's not long before the road ends on the A24 opposite Morden Hall Park. That road is (briefly) D2 here and so the junction is a LILO.
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