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The Lee Navigation is a canalised river incorporating the River Lea (River Lee). It runs from Hertford Castle Weir to the River Thames at Bow Creek; its first lock is Hertford Lock and its last Bow Locks.
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Lee Valley Park is a 10,000 acre, 26 miles long linear park, much of it green spaces, running through the northeast of London, Essex and Hertfordshire from the River Thames to Ware, through areas such as Hackney, Tottenham, Enfield, Stratford, Tower Hamlets, Walthamstow, Cheshunt, Broxbourne and Hoddesdon in an area generally known as the Lee Valley. London's largest park, Lee Valley Park is more than four times the size of Richmond Park, extending beyond London's borders into the neighbouring counties of Hertfordshire and Essex.
The park follows the course of the River Lea (Lee) along the Lea Valley from Ware in Hertfordshire through Essex and North East London, through the Queen Elizabeth Olympic Park to East India Dock Basin on the River Thames. The park is managed by Lee Valley Regional Park Authority and is made up of a diverse mix of countryside areas, urban green spaces, heritage sites, country parks, nature reserves and lakes and riverside trails, as well as leading sports centres.