The Thames Marathon Mid-Distance 9km Swim

The 9km Thames Marathon is a prestigious and demanding open-water swim that guides participants along a stunning stretch of the River Thames from Henley-on-Thames to Marlow.

🏊
9000m
📅
Sunday 9th August 2026
📍
Marlow, Buckinghamshire, UK
henleyswim.com
henleyswim.com

This point-to-point endurance challenge is renowned for its scenic beauty and varied landscapes, making it a bucket-list event for seasoned swimmers looking to push their limits.

As swimmers journey through 9km of tranquil river waters, they are treated to views of lush countryside, charming villages, and historic bridges along the way. With exceptional event organization, safety support, and a friendly atmosphere, the Thames Marathon offers a rewarding experience for those ready to tackle a true long-distance challenge. Whether chasing a personal best or savoring the journey, this iconic swim promises an unforgettable adventure on one of the UK's most famous rivers.

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The Thames Marathon Mid-Distance 9km Swim

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