Royal Windsor Triathlon
The Royal Windsor Triathlon is an annual Triathlon event held in Windsor, Berkshire, England. First organised in 1991, it is considered one of the United Kingdom's longest-running triathlons. The event takes place each June and features sprint and Olympic triathlon races.
The triathlon includes an out-and-back swim in the River Thames, an open-road cycling route passing Windsor Castle, and a multi-lap run through Windsor Great Park and along the Long Walk.
The event has attracted elite triathletes and amateur participants alike, typically drawing around 3,000–3,500 competitors. It has also hosted notable figures from other sports, including Jonny Wilkinson, Tanni Grey-Thompson, Gareth Thomas, and Jenson Button, as well as Princess Beatrice of York.
Previously organised by Human Race, the Royal Windsor Triathlon has been delivered by RunThrough since 2025, following a management transition and a new partnership with Japanese performance Sportswear brand Descente.
History
The first Royal Windsor Triathlon was held in 1991, organised by Human Race. Since its launch, the event has grown to become one of the longest-running triathlons in the UK.The triathlon has been awarded the British Triathlon Federation's "Event of the Year" seven times. The 2020 edition was cancelled due to the COVID-19 pandemic, as confirmed by the organisers. Similarly, the 2021 event did not take place, with entries automatically deferred to 2022. The triathlon resumed in 2022 with over 3,500 participants, returning as a sell-out race.
In 2025, the event transitioned to new organisers, RunThrough, as part of the company's GW Active portfolio, and announced a new partnership with Japanese performance sportswear brand Descente.
Course
As of 2025, the Royal Windsor Triathlon offers both sprint and Olympic distance races, as well as relay team options. The course is centred around Windsor and features several historic landmarks, including Windsor Castle, the River Thames, and the Long Run.Swim
The race begins east of Queen Elizabeth Bridge on the River Thames and follows an out-and-back route passing Baths Island. The sprint distance covers 750 metres, while the Olympic distance covers 1,500 metres.Bike
Following the swim, athletes transition to an open-road cycling segment through Windsor and the surrounding Berkshire countryside. The sprint course covers 22 kilometres and follows a single loop, while the Olympic course extends to 40 kilometres. The Olympic route shares the same initial section as the sprint course before branching off into a longer outer segment through additional countryside roads before returning to Windsor.Run
The run section takes participants into Windsor Great Park and along the Long Walk, offering views of Windsor Castle. The sprint run covers 5 kilometres and consists of two laps of a shorter loop, while the Olympic run covers 10 kilometres over three laps.Past winners
Olympic Triathlon (1991–2025)
Official times for winners prior to 2012 are largely unavailable due to incomplete digital records. Winner names from 1991–2011 are taken from the Royal Windsor Triathlon Wall of Fame. Verified finishing times are included where accessible.Records
The following are the current course records for the Olympic-distance event.Times from 2012 are excluded, as the event was run as a duathlon due to unsafe swim conditions in the River Thames.
Controversies
Horse–cyclist collision (2018)
During the 28th Royal Windsor Triathlon on 17 June 2018, a cyclist collided with a horse and rider on the open-road bike course. The incident was captured on helmet-mounted camera and circulated widely online, showing the cyclist riding too close, touching the horse's stirrup, and causing the animal to rear. This resulted in a bruised ankle for the rider and a missing horseshoe.The race organisers, Human Race, issued a public apology and launched an internal review. They stated they had identified two individuals responsible, although their identities were withheld due to ongoing police investigations. One cyclist received a lifetime ban from Human Race events, and another athlete, who came forward voluntarily, was given a 12-month ban.
River Thames water quality concerns (2024)
During the 32nd Royal Windsor Triathlon on 9 June 2024, at least 35 competitors reported falling severely ill after completing the swimming leg in the River Thames. Affected participants sought medical treatment in hospitals.Race organisers Human Race responded by stating that the river water had been tested in the weeks leading up to the event and again on race day, and that all tests were within British Triathlon Federation safety standards.
Thames Water, the utility company, cautioned against assigning blame solely to its operations. It highlighted that river health can be affected by multiple factors, including agricultural runoff, wildlife, and road drainage. The company also noted that its nearest sewage treatment plant in Slough had not discharged since early April.