ATW Stewartby Lake Triathlon
Stewartby, Bedford, United Kingdom · June · Independent (ATW Events)
Why people love it
- Lake safety team praised by a nervous first-timer; sprint swim is 750 m (0.47 mi)
- Flat, fast lapped bike, easy to navigate; 20 km (12.4 mi) for the sprint
- Out-and-back run beside the lake lets clubmates cheer each other
- Racecheck 4.68 out of 5 across 31 reviews; marshals and commentator praised
Watch out for
- Two reviewers reported cars on the bike route; one called overtaking dangerous
- Run is gravel and trail, not tarmac, over 5 km (3.1 mi) or 10 km (6.2 mi)
- One reviewer found the swim slightly long and choppy, with unclear buoys 2 to 3
- Olympic bike is about 37 km (23 mi) per Racecheck, shorter than the usual 40 km (25 mi)
Race
How racers feel about it, how well it is run, and how it treats a first timer. Counts for 30% of the overall score.
Toughness: Moderate
- Racer satisfactionLoved4.3
Racecheck averages 4.68 out of 5 on 31 reviews, 4.19 in 2026; praise for marshals, finish area and commentator. · Medium confidence
- OrganizationFlawless4.5
Finish area 4.88, logistics 4.87 and staff 4.81 on Racecheck; one reviewer found the event area unclear. · Medium confidence
- First timer friendlyIdeal first race4.7
Welcoming; one lap swim · Medium confidence
Course traits, not part of the score
- PR potentialFast4.3
Flat · Medium confidence
Swim
Wetsuit odds, water temperature, calm, and the experience of the start. Counts for 16% of the overall score.
- Wetsuit legalUsually4.4
June UK lake; Triathlon England forbids wetsuits above 24.6 °C (76.3 °F); hire offered · Low confidence
- Water temperatureAcceptable3.3
Water temperature not published; June lake likely cool · Low confidence
- Calm waterSome chop3.0
One reviewer called it slightly choppy on an open lake · Low confidence
- Swim easeEasy3.6
750 m (0.47 mi) single lap · Low confidence
- Swim experienceGreat3.9
Lake safety team praised; water quality 4.53 · Medium confidence
- Swim supportAbundant4.5
Safety team helped a nervous first-timer · Medium confidence
Bike
Road surface, closures, scenery and wind. Counts for 18% of the overall score.
- Road surfaceGood3.5
No complaints noted · Low confidence
- Road closuresMostly open2.4
Two reviewers reported cars on the bike route and one called overtaking dangerous. · Medium confidence
- Bike sceneryPleasant2.8
Flat road loop; reviewers say little about the views. · Low confidence
- WindSome wind3.0
Open flat ground; no wind comments in the reviews. · Low confidence
Course traits, not part of the score
- Bike speedFast4.4
Fast · Medium confidence
- Bike flatnessPancake flat4.6
Flat · Medium confidence
- Bike simplicityMostly simple4.0
Out and back loop with turnarounds, easy to navigate · Medium confidence
Run
Crowds, aid stations, conditions underfoot and scenery. Counts for 13% of the overall score.
- Crowd supportStrong3.5
Out and back lets clubmates see each other, and a commentator was praised. · Medium confidence
- Aid stationsGood4.1
Aid stations 4.57 · Medium confidence
- Run sceneryBeautiful3.8
Reviewers call the lake path scenic. · Medium confidence
- Run conditionsEasy3.8
Flat gravel and trail for 5 km (3.1 mi). · Medium confidence
Course traits, not part of the score
- Run flatnessFlat4.7
Flat · Medium confidence
Conditions
Air temperature, how predictable the weather is, setting, and spectating. Counts for 13% of the overall score.
- Air temperaturePleasant3.9
June morning, roughly 12 to 22 °C (54 to 72 °F) · Low confidence
- Weather reliabilityVariable3.0
British summer · Low confidence
- Venue beautyLovely3.6
Country park lake setting with a wind turbine and clay-pit history. · Medium confidence
- Spectator friendlyEasy4.2
Lapped bike and out-and-back run · Medium confidence
Course traits, not part of the score
- Low altitudeSea level5.0
About 30 m (100 ft) · High confidence
Stay and travel
Hotels, walkability, getting there, and the town around the race. Counts for 10% of the overall score.
- Hotel availabilityGood4.0
Bedford nearby · Low confidence
- Hotel valueGood3.5
No evidence · Low confidence
- WalkabilityWalkable4.0
Car park opposite the venue; excellent facilities · Medium confidence
- Travel easeEasy3.8
Luton Airport and Stewartby station nearby · Low confidence
- LogisticsSimple4.3
Logistics 4.87; one venue; one reviewer found the event area unclear · Medium confidence
- Town and foodFine2.8
Rural village; Bedford is a short drive. · Low confidence
Key facts
- Location
- Stewartby, Bedford, Bedfordshire, United Kingdom
- Typical month
- June
- Latest or next date
- 20 June 2027
- Organiser
- Independent (ATW Events)
- Distances
- 0.8 km (0.5 mi) swim, 20 km (12.4 mi) bike, 5 km (3.1 mi) run
- Swim venue
- Stewartby Lake, Marston Vale Country Park (Stewartby Sailing Club) (lake)
- Wetsuit
- Likely legal; wetsuit hire offered (Triathlon England follows World Triathlon, no wetsuit above 24.6 °C / 76.3 °F for swims up to 1,500 m)
- Swim laps
- 1
- Bike laps
- 2
- Air temperature
- 12–22 °C (54–72 °F)
- Altitude
- 30 m (98 ft)
- Nearest airport
- London Luton Airport
- Where to stay
- Bedford
- Booking
- Day-trip race. Parking in the event car park opposite the venue for a small charge.
What racers and reviewers say
- Racecheck Stewartby Lake TriathlonRaced 2026 · aggregator · Positive
31 athletes average 4.68 out of 5; the 2026 average is 4.19. Ten reviews shown split five sprint, four standard and one aquabike. Reviewers praise organisation, marshals, finish area and commentator, and call it welcoming for first-timers. The bike is fast and flat but two reported car traffic, one calling overtaking dangerous. The run is gravel with no tarmac. Count is pro rata excluding aquabike.
“Very beginner friendly event”
- ATW Events organiser pageRaced 2027 · article · Positive
The organiser describes a lake swim, lapped road bike and a flat run on paths in Marston Vale Country Park; parking is across the road for a small fee. The 2023 edition was a sold-out GB team qualifier.
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Sources
Pages we used for facts and ratings. See how we rate.
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