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The Greenway is the name given in the early 21st century to the path along the top of the London Northern Outfall Sewer from Stratford Marsh TQ371839 to Beckton TQ439820, a distance of approximately 8km. For most of its route the path has the status of a permissive footpath but is also well used by cyclists without hindrance. The presence of the sewer beneath is not made prominent, but one gets an occasional smell of it. The path is unlit and therefore not a safe place to be at night, but generally safe enough in daytime.

The River Lea (or Lee) originates at Marsh Farm Leagrave, Luton in the Chiltern Hills and flows generally southeast, east, and then south to London where it meets the River Thames. The river is 42 miles long.
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