The 5.5km Thames Marathon is a challenging and scenic open-water swim that takes participants on a spectacular journey along the River Thames from Henley-on-Thames to Marlow.
Known for its picturesque route and point-to-point format, this long-distance swim offers a rewarding test of stamina and skill through some of the most beautiful stretches of the Thames.
Swimmers navigate tranquil, meandering waters flanked by lush countryside, charming riverside towns, and historic landmarks. With excellent event organization and a supportive atmosphere, the Thames Marathon is perfect for experienced swimmers seeking a memorable endurance challenge. Whether aiming for a fast time or simply soaking in the views, the 5.5km Thames Marathon delivers an unforgettable open-water experience.
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