Tucked into a corner besides the M25/A30 junction and little more than a stone-throw from Heathrow Airport is the surprisingly tranquil Heron Lake. We visited on a wet and windy Monday evening, so possibly not the best occasion to get a good impression, yet we were impressed.
Being just two minutes off Junction 13 of the M25, the lake is easy to get to, as long as traffic is flowing on the motorway! It can also be reached by bike on the relatively quiet (by London standards) B376.