The B307 was a short B-road on Putney Heath.
It started on the A3 and headed northeast for a short distance across the heath to end on the A3210.
Like the A3210, the B307 is more than just unclassified. The northern end, now part of Wildcroft Road, is still accessible to traffic but the road just ends for no apparent reason just past the gates to Wildcroft Manor and becomes a footpath through the wood. It is now impossible to tell where it used to meet the A3 as the terrain has changed so much and the footpath has moved off the ex-A307 by this point (although there is a speed camera in roughly the right place).
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