London's most famous urban chalkstream: a short, intimate, heavily restored river flowing from the chalk-fed headwaters around Croydon and Carshalton through Morden, Wimbledon and Wandsworth to the Thames. Once written off as ecologically dead, it now supports brown trout again alongside a proper mixed coarse fishery. The appeal is not grand private-chalkstream elegance but close-quarters stalking, tricky little glides, undercut banks, bridge water, public-park access and a strong conservation story.
- Chalk