Sun 10 Aug 2025 Marlow, Buckinghamshire, UK

Thames Marathon | Half Marathon Swim

A long-distance swimming marathon with multiple distances and feed stations from Henley-on-Thames to Marlow.

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Event overview

The Thames Marathon is an endurance swim between Henley-on-Thames and Marlow with a choice of 3 distances and a relay option. The swims cover a beautiful stretch of the Thames and has become one of open water swimming’s most prestigious marathon swims. The Event Village, registration and the finish are in Higginson park in Marlow. Swimmers are transported to the start in coaches from here to start their event, swimming back to Marlow. There is also the option to walk or run to the start of the half-marathon.

Charity places

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Event details

  • All fitness levels
  • Dogs allowed
  • Event village
  • Free venue entry
  • Newcomers
  • Spectators
  • Traders at event

  • Bag storage
  • Bar
  • BBQ
  • Changing facilities
  • Paid parking
  • Toilets

Event HQ

Higginson Park, Marlow
High Street
Marlow
Buckinghamshire
SL7 1AW
UK

Map

Click to open in map

What3words

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Route

  • Cut off time
  • Food stations
  • Wave start

Sustainability

  • Recycling