Starting at South Woodham Ferrers, competitors follow the northern bank of River Crouch until it meets the North Sea, before turning left through the remote Dengie Marshes and onwards to Bradwell-on-Sea at the mouth of the Blackwater Estuary. An overnight stop at Steeple will offer brief respite until the morning when the participants will cover the remaining 37 miles through the historical riverside town of Maldon then towards Tollesbury. The final sting in the tail of the challenge is the 5 miles loop around the edge of RSPB Old Hall Marshes nature reserve, finishing at the hamlet of Salcott-cum-Virley
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