Best Olympic-distance triathlons in the United Kingdom
53 rated races, ranked by an overall score built from racer reviews and race reports. How we rate
53 races
By the numbers
Overall score 4.4Very good#3 of 164Strong evidence · 4 sources + 206 runner ratings
Water 16–19 °C (61–66 °F)
1. Eastbourne Triathlon and Multisport Festival
Overall score 4.4Very goodStrong evidence · 4 sources + 206 runner ratingsTop 2%#3 of 164 overallEastbourne, United Kingdom · Last race 12 Jul 2026
1.5 / 36.6 / 10 kmRacers loveSea swim from the beach with Eastbourne pier behind
Watch outSea swim can be cancelled for wind and chop, as in 2024
“Really well organised, with a great vibe” Racecheck reviewers, Racecheck: Eastbourne Triathlon and Multisport…
- Water
- 16–19 °C (61–66 °F)
- Air
- 15–23 °C (59–73 °F)
- Bike climb
- 680 m (2,230 ft)
- Field
- about 1,300
- Best
- Race 4.6
- Weakest
- Swim 3.0
2. Cotswolds Lake 62 Triathlons (Sprint, Standard and Super Sprint)
Ashton Keynes (Cotswold Water Park), United Kingdom
Usually May
Overall score 4.3Very good#4 of 164Strong evidence · 2 sources + 258 runner ratings
Water 15–21 °C (59–70 °F)
2. Cotswolds Lake 62 Triathlons (Sprint, Standard and Super Sprint)
Overall score 4.3Very goodStrong evidence · 2 sources + 258 runner ratingsTop 3%#4 of 164 overallAshton Keynes (Cotswold Water Park), United Kingdom · Usually May
1.5 / 40 / 9 kmRacers loveCalm private lake with free parking about a 5 minute walk from transition.
Watch outThe lake is weedy in summer; reviewers mention it on all three pages.
“Really friendly enjoyable for a tri virgin” Racecheck verified participants (130 reviews), Racecheck (Cotswolds Lake 62 Individual Team…
- Water
- 15–21 °C (59–70 °F)
- Air
- 12–22 °C (54–72 °F)
- Best
- Race 5.0
- Weakest
- Bike 2.9
Overall score 4.3Very good#5 of 164Strong evidence · 5 sources + 349 runner ratings
Water 19–22 °C (66–72 °F)
3. Cholmondeley Castle Triathlon (Castle Series)
Overall score 4.3Very goodStrong evidence · 5 sources + 349 runner ratingsTop 3%#5 of 164 overallMalpas, United Kingdom · Next race 26 Jun 2027
1.5 / 42 / 10 kmRacers loveFinish across the main lawn at Cholmondeley Castle.
Watch outSwim water is dark and weedy with poor visibility.
“Great event in a beautiful location” Racecheck reviewers, Racecheck: Cholmondeley Castle Triathlon Series
- Water
- 19–22 °C (66–72 °F)
- Air
- 12–24 °C (54–75 °F)
- Field
- about 1,500
- Best
- Race 4.6
- Weakest
- Stay and travel 3.0
Overall score 4.3Very good#6 of 164Moderate evidence · 2 sources + 91 runner ratings
Water 15–18 °C (59–64 °F)
4. English Riviera Triathlon
Overall score 4.3Very goodModerate evidence · 2 sources + 91 runner ratingsTop 4%#6 of 164 overallTorquay, United Kingdom · Next race 4 Jul 2027
Racers loveFully closed-road bike on 5 km (3.1 mi) laps; the organiser says it is the only closed-road triathlon in…
Watch outThe sprint is drafting-legal from 2026; the standard is non-drafting.
- Water
- 15–18 °C (59–64 °F)
- Air
- 16–22 °C (61–72 °F)
- Best
- Run 4.9
- Weakest
- Stay and travel 3.5
Overall score 4.0Very good#9 of 164Thin evidence · 2 sources + 28 runner ratings
Water 14–16 °C (57–61 °F)
5. The Original Swanage Triathlon Festival
Overall score 4.0Very goodThin evidence · 2 sources + 28 runner ratings#9 of 164 overallSwanage, United Kingdom · Next race 27 Jun 2027
1.5 / 38 / 10 kmRacers loveSea swim in Swanage Bay, kayak-guided, with beach views and reported clear water
Watch outBoth bike and run are hilly; the run includes a steep climb most walk
“Some of the best marshals I've ever experienced.” Racecheck participants, Racecheck (28 verified reviews)
- Water
- 14–16 °C (57–61 °F)
- Air
- 14–20 °C (57–68 °F)
- Best
- Race 5.0
- Weakest
- Swim 3.4
Overall score 4.0Very good#12 of 164Moderate evidence · 1 source + 102 runner ratings
Water 16–19 °C (61–66 °F)
6. Bournemouth International Triathlon
Overall score 4.0Very goodModerate evidence · 1 source + 102 runner ratingsTop 8%#12 of 164 overallBournemouth, United Kingdom · Next race 12 Sep 2027
Racers loveSea swim from a Blue Flag beach beside the pier, with many marshals on the water
Watch outBike is mostly dual carriageway; one 2025 reviewer reported 70 mph (113 km/h) traffic and thin signage
- Water
- 16–19 °C (61–66 °F)
- Air
- 14–20 °C (57–68 °F)
- Best
- Run 5.0
- Weakest
- Bike 2.5
7. The Weymouth Classic & Sprint Triathlon (WMD Triathlon)
Weymouth, United Kingdom
Next race 6 Jun 2027
Overall score 3.9Very good#13 of 164Moderate evidence · 1 source + 139 runner ratings
Water 14–17 °C (57–63 °F)
7. The Weymouth Classic & Sprint Triathlon (WMD Triathlon)
Overall score 3.9Very goodModerate evidence · 1 source + 139 runner ratingsTop 8%#13 of 164 overallWeymouth, United Kingdom · Next race 6 Jun 2027
1.5 / 38.6 / 9.9 kmRacers loveSheltered bay swim with kayaks and rescue boats on every course
Watch outSwim exit is about 450 m (490 yd) from transition: bring old shoes for the run
“Hard to fault the event.” Eventrac participants, Eventrac reviews, WMD Triathlon (139 written…
- Water
- 14–17 °C (57–63 °F)
- Air
- 12–20 °C (54–68 °F)
- Bike climb
- 321 m (1,050 ft)
- Best
- Race 4.7
- Weakest
- Bike 3.0
Overall score 3.8Very good#15 of 164Thin evidence · 1 source + 53 runner ratings
8. Bedford Triathlon
Overall score 3.8Very goodThin evidence · 1 source + 53 runner ratings#15 of 164 overallBedford, United Kingdom · Next race 15 Aug 2027
Racers loveTown-centre river swim at The Embankment with an exit ladder.
Watch outPondweed and duckweed in the river forced a moved start in 2026.
“Marshals, support and encouragement around the course were all excellent” 53 Racecheck reviewers, Racecheck (Bedford Triathlon)
- Air
- 13–23 °C (55–73 °F)
- Best
- Race 4.8
- Weakest
- Bike 3.0
9. Sandman Triathlon (Superfeet Sandman, Always Aim High)
Newborough, United Kingdom
Last race 27 Sep 2026
Overall score 3.8Very good#18 of 164Thin evidence · 3 sources + 17 runner ratings
Water 13–16 °C (55–61 °F)
9. Sandman Triathlon (Superfeet Sandman, Always Aim High)
Overall score 3.8Very goodThin evidence · 3 sources + 17 runner ratings#18 of 164 overallNewborough, United Kingdom · Last race 27 Sep 2026
1.5 / 42.3 / 10.2 kmRacers loveBeach start and swim facing Snowdonia, then up through the dunes to the event village.
Watch outDistances are non-standard: the sprint bike is about 22.9 km (14.2 mi), the Standard bike 42.3 km (26.3 mi).
“Everything was so well set up and well organised.” Racecheck participants, Racecheck (21 verified reviews)
- Water
- 13–16 °C (55–61 °F)
- Air
- 8–17 °C (46–63 °F)
- Field
- about 500
- Best
- Run 4.6
- Weakest
- Stay and travel 2.7
Overall score 3.8Very good#21 of 164Thin evidence · 1 source + 54 runner ratings
10. Bishopton Triathlon
Overall score 3.8Very goodThin evidence · 1 source + 54 runner ratings#21 of 164 overallStockton-on-Tees, United Kingdom · Next race 22 Aug 2027
1.5 / 42 / 10 kmRacers loveLake no deeper than 1.5 m (5 ft), so most of the swim is standable.
Watch outRun is gravel and uneven grass, not ideal for a personal best.
“super beginner friendly” 54 Racecheck reviewers, Racecheck (Bishopton Triathlon)
- Air
- 12–21 °C (54–70 °F)
- Best
- Stay and travel 4.5
- Weakest
- Bike 2.9
Overall score 3.8Very good#22 of 164Thin evidence · 2 sources + 28 runner ratings
11. ATW Stewartby Lake Triathlon
Overall score 3.8Very goodThin evidence · 2 sources + 28 runner ratings#22 of 164 overallStewartby, Bedford, United Kingdom · Next race 20 Jun 2027
1.5 / 37 / 10 kmRacers loveLake safety team praised by a nervous first-timer; sprint swim is 750 m (0.47 mi)
Watch outTwo reviewers reported cars on the bike route; one called overtaking dangerous
“Very beginner friendly event” Racecheck reviewers (31), Racecheck Stewartby Lake Triathlon
- Air
- 12–22 °C (54–72 °F)
- Best
- Race 4.9
- Weakest
- Bike 2.5
12. Windermere Triathlons and Multisport Weekend
Bowness-on-Windermere, United Kingdom
Next race 10 Jul 2027
Overall score 3.8Very good#23 of 164Moderate evidence · 3 sources + 37 runner ratings
Water 15–19 °C (59–66 °F)
12. Windermere Triathlons and Multisport Weekend
Overall score 3.8Very goodModerate evidence · 3 sources + 37 runner ratingsTop 14%#23 of 164 overallBowness-on-Windermere, United Kingdom · Next race 10 Jul 2027
1.5 / 48 / 10 kmRacers loveClear-water swim in Lake Windermere from Cockshott Point; wetsuit optional but recommended.
Watch outDark red swim buoys are hard to sight; reviewers want more and brighter ones.
“Suits novices and pros.” 36 written reviews, July 2026, Eventrac / Wild Deer Events reviews
- Water
- 15–19 °C (59–66 °F)
- Air
- 12–20 °C (54–68 °F)
- Best
- Conditions 4.0
- Weakest
- Stay and travel 2.7
Overall score 3.7Very good#25 of 164Moderate evidence · 1 source + 90 runner ratings
13. Reading Triathlon
Overall score 3.7Very goodModerate evidence · 1 source + 90 runner ratingsTop 16%#25 of 164 overallPingewood, Reading, United Kingdom · Next race 12 Sep 2027
1.5 / 40 / 10.8 kmRacers loveMarshals and staff are praised by most reviewers.
Watch outWeed in the lake slowed some swimmers in 2025 and 2026.
“Really friendly and supportive marshals” 90 Racecheck reviewers, Racecheck (Reading Triathlon)
- Air
- 11–20 °C (52–68 °F)
- Best
- Race 4.5
- Weakest
- Bike 3.2
Overall score 3.7Very good#26 of 164Moderate evidence · 4 sources
Water 17–21 °C (63–70 °F)
14. Dorney Lake Triathlon
Overall score 3.7Very goodModerate evidence · 4 sourcesTop 16%#26 of 164 overallEton Dorney, United Kingdom · Last race 3 Oct 2026
1.5 / 38 / 10 kmRacers loveCalm, clear Olympic rowing lake with a simple 750 m (820 yd) rectangular swim.
Watch outOpen lake is exposed: expect a headwind on one side of each 5 km (3.1 mi) loop.
“well organised” Peter G., Racecheck
- Water
- 17–21 °C (63–70 °F)
- Air
- 14–24 °C (57–75 °F)
- Bike climb
- 3 m (10 ft)
- Field
- about 1,500
- Best
- Bike 4.3
- Weakest
- Run 2.8
Overall score 3.7Very good#28 of 164Moderate evidence · 3 sources + 34 runner ratings
15. The Huntsman Triathlon
Overall score 3.7Very goodModerate evidence · 3 sources + 34 runner ratingsTop 17%#28 of 164 overallRingwood, United Kingdom · Last race 24 May 2026
1.1 / 33 / 10 kmRacers loveMass-start lake swim in Ellingham Lake; Racecheck water quality 4.90 out of 5
Watch outStandard distance is 1.1 km (0.7 mi), 33 km (20.5 mi), 10 km (0.68, 20.5, 6.2 mi), short of a full Olympic
“Ponies, donkeys and foals on the roads” Racecheck reviewers (57), Racecheck The Huntsman Triathlon
- Air
- 10–20 °C (50–68 °F)
- Best
- Swim 3.9
- Weakest
- Run 3.0
Overall score 3.7Very good#29 of 164Thin evidence · 2 sources + 18 runner ratings
16. Dambuster Triathlon (Rutland Water)
Overall score 3.7Very goodThin evidence · 2 sources + 18 runner ratings#29 of 164 overallOakham, United Kingdom · Last race 21 Jun 2026
Racers loveSheltered creek swim with clear water, calm in most reports
Watch outBike has short sharp climbs; ride similar hills before race day
“Super clear water for the swim.” Racecheck
- Air
- 12–22 °C (54–72 °F)
- Best
- Race 4.3
- Weakest
- Run 3.2
Overall score 3.7Very good#32 of 164Thin evidence · 3 sources + 30 runner ratings
Water 13–20 °C (55–68 °F)
17. ATW St Neots Triathlon (Series)
Overall score 3.7Very goodThin evidence · 3 sources + 30 runner ratings#32 of 164 overallSt Neots, United Kingdom · Next race 2 May 2027
1.5 / 45 / 10 kmRacers loveRacecheck rates the three races 4.5 to 4.6 out of 5 across 112 ratings, with marshals praised.
Watch outFive reviewers reported illness after the river swim in 2024 and 2025; the organiser says water tests passed.
“This is the one to do if you're a novice” Racecheck St Neots Triathlon Series Race 1
- Water
- 13–20 °C (55–68 °F)
- Air
- 8–22 °C (46–72 °F)
- Best
- Race 4.6
- Weakest
- Bike 2.8
Overall score 3.6Very good#35 of 164Moderate evidence · 3 sources + 25 runner ratings
Water 15–18 °C (59–64 °F)
18. Big Lime Triathlons Hartlepool Marina
Overall score 3.6Very goodModerate evidence · 3 sources + 25 runner ratingsTop 22%#35 of 164 overallHartlepool, United Kingdom · Next race 8 Aug 2027
Racers loveMarina swim with many lifeguards; reviewers call it safe and good for beginners.
Watch outRoadworks and marina building work disturbed transition and the view in 2026.
“Flat course, so safe and fast.” 25 written reviews, August 2026, Eventrac / Wild Deer Events reviews
- Water
- 15–18 °C (59–64 °F)
- Air
- 13–20 °C (55–68 °F)
- Field
- about 103
- Best
- Swim 4.1
- Weakest
- Bike 3.0
Overall score 3.6Very good#37 of 164Moderate evidence · 7 sources
Water 16–19 °C (61–66 °F)
19. Hever Castle Triathlon (Castle Race Series)
Overall score 3.6Very goodModerate evidence · 7 sourcesTop 22%#37 of 164 overallHever, United Kingdom · Next race 25 Sep 2027
Racers loveSwim starts at the castle loggia in a sheltered lake of about 15 ha (38 acres)
Watch outBike is never flat: climbs start 2 km (1.2 mi) in, and the Olympic does two laps
“unforgiving but fun hilly bike” Castle Race Series: Hever Castle 2025 report
- Water
- 16–19 °C (61–66 °F)
- Air
- 10–19 °C (50–66 °F)
- Field
- about 500
- Best
- Conditions 4.2
- Weakest
- Stay and travel 2.8
20. Roadford Lake Triathlon
Roadford Lake, Broadwoodwidger, Lifton, United Kingdom
Next race 16 May 2027
Overall score 3.6Very good#38 of 164Strong evidence · 6 sources + 162 runner ratings
Water 12–15 °C (54–59 °F)
20. Roadford Lake Triathlon
Overall score 3.6Very goodStrong evidence · 6 sources + 162 runner ratingsTop 24%#38 of 164 overallRoadford Lake, Broadwoodwidger, Lifton, United Kingdom · Next race 16 May 2027
1.5 / 46 / 10 kmRacers loveRacecheck rates it 4.5 of 5 from 162 reviews; staff and logistics both above 4.7.
Watch outBike is rolling to hilly on open rural roads; reviewers report potholes and no closed roads.
- Water
- 12–15 °C (54–59 °F)
- Air
- 9–17 °C (48–63 °F)
- Bike climb
- 580 m (1,900 ft)
- Field
- about 200
- Best
- Race 4.5
- Weakest
- Bike 2.5
21. #51fiver Cotswold Standard Distance Triathlon (I-Compete)
Ashton Keynes (Cotswold Water Park, Lake 32), United Kingdom
Next race 16 May 2027
Overall score 3.6Very good#40 of 164Thin evidence · 1 source + 10 runner ratings
21. #51fiver Cotswold Standard Distance Triathlon (I-Compete)
Overall score 3.6Very goodThin evidence · 1 source + 10 runner ratings#40 of 164 overallAshton Keynes (Cotswold Water Park, Lake 32), United Kingdom · Next race 16 May 2027
Racers loveRacecheck rates it 4.71 out of 5 on 59 ratings; 86% of reviews say ideal for beginners.
Watch outRoads are open to traffic; a delayed start in 2025 brought busier roads.
“A great race for first timer at this distance.” Racecheck #51fiver Cotswold Tri
- Air
- 8–18 °C (46–64 °F)
- Best
- Race 4.9
- Weakest
- Bike 2.8
Overall score 3.6Very good#41 of 164Moderate evidence · 3 sources + 52 runner ratings
Bike climb 170 m (560 ft)
22. Box End Triathlon
Overall score 3.6Very goodModerate evidence · 3 sources + 52 runner ratingsTop 24%#41 of 164 overallBedford, United Kingdom · Next race 23 May 2027
Racers loveClear lake with kayak support; Racecheck rates water quality 4.62 of 5.
Watch outBike roads are open; 2025 reviewers report busy traffic and congestion.
“Every aspect worked well.” 39 Racecheck reviewers (10 shown, 2024 to 2026), Racecheck
- Air
- 9–19 °C (48–66 °F)
- Bike climb
- 170 m (560 ft)
- Best
- Race 4.3
- Weakest
- Bike 2.6
Overall score 3.6Very good#45 of 164Thin evidence · 2 sources + 9 runner ratings
23. Arundel Lido Triathlon
Overall score 3.6Very goodThin evidence · 2 sources + 9 runner ratings#45 of 164 overallArundel, United Kingdom · Next race 16 May 2027
0.8 / 37 / 9 kmRacers loveHeated open-air lido swim with a castle backdrop
Watch outThe standard is short: 800 m (0.5 mi) swim, 37 km (23 mi) bike, 9 km (5.6 mi) run
- Air
- 8–17 °C (46–63 °F)
- Best
- Swim 4.4
- Weakest
- Bike 3.2
24. New Forest Triathlon (Challenging Events)
Ringwood (Moyles Court), United Kingdom
Last race 6 Sep 2026
Overall score 3.6Very good#46 of 164Thin evidence · 2 sources + 10 runner ratings
24. New Forest Triathlon (Challenging Events)
Overall score 3.6Very goodThin evidence · 2 sources + 10 runner ratings#46 of 164 overallRingwood (Moyles Court), United Kingdom · Last race 6 Sep 2026
1.1 / 33 / 10 kmRacers loveBike runs through the New Forest, with ponies and cattle on the roads and marshals at every turn.
Watch outThe standard distance is 1.1 km (0.68 mi) swim, 33 km (20.5 mi) bike, 10 km (6.2 mi) run.
“Recommended for all levels of experience.” Racecheck reviewers (84 ratings), Racecheck New Forest Middle Distance Triathlon
- Air
- 11–20 °C (52–68 °F)
- Best
- Race 3.9
- Weakest
- Stay and travel 2.5
About these ratings
Races are ranked by an overall score out of 5, built from racer reviews and race reports, on the race itself, swim, bike, run, conditions and travel. 5 is always the better end. How we rate
Olympic course: 1.5 km (0.9 mi) swim, 40 km (24.9 mi) bike, 10 km (6.2 mi) run.
Reports on Olympic-distance races are scarcer, so 31 of 53 scores are thin evidence: fewer than 4 sources each (dashed score, marked provisional). Show only races with 4+ sources. 34 of these races set their own distances, and each race page lists the real course.
130 racer reviews and race reports.
Browse all 53 races, A to Z
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