Pickle Ditch, also known as the Pickle, is a minor, 0.9-kilometre (0.56 mi)[1] long stream—brook—in the locality of Colliers Wood in the London Borough of Merton, Greater London, England.[2] Rising from the River Wandle, a tributary of the River Thames, and flowing back into it, Pickle Ditch is the last remaining course of the River Wandle's original course through Merton, before the other sections were straightened.[3]