Thames Marathon Swim

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From Henley Swim

  • Date Sun 10th August 2025
  • Time 07:00
  • Location Marlow, Buckinghamshire
  • Price £103.50 - £204.50
  • Races 4 races
  • Distances Marathon, Half Marathon

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Booked 6 times recently

Event summary

Get ready for an exhilarating day of open water swimming at the Thames Marathon Swim, organized by Henley Swim, taking place on Sunday, August 10th, 2025, in the picturesque town of Marlow, Buckinghamshire. Known for its stunning scenery and vibrant atmosphere, this prestigious event has earned accolades, including being rated the Top-Rated swim by Racecheck and winning several gold awards.

Swimmers can choose from a variety of race distances, including the full 13km marathon swim, a 9km mid-distance challenge, or a 5.5km half marathon, all set against the breathtaking backdrop of the River Thames. Participants will navigate through sections at three different locks, where refreshments will be provided to keep everyone energized. For those looking for a team experience, the Thames Marathon Relay allows three swimmers to tackle the full distance together in a fun and engaging way.

The event village is conveniently located at Higginson Park, where spectators can enjoy the vibrant atmosphere while cheering on their favorite swimmers. With transport provided to the starting points and a beautiful route back to Marlow, this event promises excitement for both participants and supporters alike. Don’t miss out on this chance to be part of one of the most celebrated swims in

Thames Marathon Swim

Sun 10th August 2025

Swimmers with brightly colored swim caps and buoys navigate the Thames River during the Thames Marathon, surrounded by waterfront houses and lush green trees. The event logo is visible in the lower-left corner. A riverside pavilion with a rotunda and large windows stands among lush green trees. In the river in front, numerous swimmers in brightly-colored swim caps and buoy markers participate in an open water swimming event. Four people pose together in front of orange inflatable markers labeled "ZONE3" at an outdoor event. They are standing on grass near a body of water with buildings in the background. Two women are on the left, wearing swimsuits, and two men are on the right, in athletic wear. A group of smiling swimmers in wetsuits sit on a bus, waving towards the camera. They appear cheerful and ready for their activity. The bus interior has blue seats, and the outside greenery is visible through the windows. Two swimmers in wetsuits and orange swim caps pose for a photo in front of a busy outdoor swimming event. The woman on the left wears a black dhb wetsuit, and the man on the right wears a black Orca wetsuit. Others prepare for the event in the background. Three men in swim gear, including swim caps and wetsuits for two of them, stand on a street lined with brick buildings. One man in colorful swim briefs is between the others who wear black wetsuits. All smile and give a thumbs-up gesture. A large group of swimmers in wetsuits and colorful swim caps gather at the edge of a body of water, preparing for a swim event. Spectators and organizers are seen on the shore, some holding equipment, while a person on a paddleboard appears to give instructions. A group of people pose happily for a photo in front of a "Thames Marathon" banner, celebrating their participation. Some wear medals around their necks and athletic attire. Behind them is a scenic riverside with boats on the water and trees in the background.

Organiser's Description

CURRENTLY ON EARLY BIRD PRICES!

The Thames Marathon has been previously rated the Top-Rated swim by Racecheck, and has won several gold awards! It has become one of open water swimming's most prestigious and well-known swims, attracting swimmers from all around the world as well as many locally. The swims are split into sections, due to the locks on the river, which make them manageable for many types of swimmer.

The event has several swim options on the same day, taking place on an incredibly stunning stretch of the River Thames between Henley-on-Thames and Marlow.

-The full Thames Marathon - 13km swim - The swim is split into 4 sections. Swimmers will be required to exit the water at the 3 locks (Hambleden, Hurley and Temple ) where drinks and energy snacks will be available.

-The Mid-Distance - 9km - The swim is split into 3 sections. Swimmers will be required to exit the water at the 2 locks (Hurley and Temple) where drinks and energy snacks will be available.

-The Half Marathon - 5.5km - The swim is split into 3 sections. Swimmers will be required to exit the water at the 2 locks (Hurley and Temple) where drinks and energy snacks will be available

-The Thames Marathon Relay - 13km between 3 swimmers - each swimmer will swim a 4/5km section while the other two walk it, finishing all together at the end in Marlow.

The Event Village and Parking is at Higginson Park in Marlow. Swimmers will be transported by coach to the start of each distance and will swim back to Marlow. There is also the option to walk or run to the start of the Half Marathon.

This event is fantastic for spectators/ supporters as the finish is in a central park in the stunning town of Marlow, the Thames path is a lovely walk, and there is an amazing vibe.

Races

  • Thames Marathon Swim (13km)

    Wetsuit Place

    £138.50

    Booking for more than 1?
  • Thames Half Marathon Swim (5.5km)

    £103.50

    Booking for more than 1?
  • Thame Mid-Distance Swim (9km)

    Wetsuit Place

    £123.50

    Booking for more than 1?
  • Thames Marathon3-Person Relay Swim (4km/5km/4km)

    £204.50

Reviews

  • 5
  • 4
  • 3
  • 2
  • 1

4.8

3 reviews

LN
Luke

·a year ago

Lovely bunch of people. Well organised. Everything seems smooth and fast. Excellent food stations. Water entrance and exit at some places could be better. And toilets wanted at break areas. Overall, brilliant and from what I hear they improve every year
MH
Mark

·a year ago

Great Event. Very Well Organised. Super friendly Event
JW
Julie

·5 years ago

Well Organised. Long swim but felt very well looked after both before, during and after event. Help getting out at locks, great variety at food stops and plenty kayak/safety support.

Location

Higginson Park, Pound Lane, Marlow, SL7 2AE, United Kingdom

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