IRONMAN 70.3 Shanghai Chongming
Chongming Island (Bright Tian Yuan, Mingzhu Lake Park), China · May · IRONMAN
Why people love it
- Flat, fast course: 3:38:03 winning time in 2025
- Self-seeded lake swim at around 21 °C (70 °F)
- 50 age-group slots for the 70.3 Worlds
- More aid stations and medical support added for 2026
Watch out for
- No first-person athlete reviews found, so scores lean on press material
- Warm and humid: May highs reach 31 °C (88 °F)
- Wind exposure on the flat island is likely but unconfirmed
- Most lodging is in Shanghai city, a transfer away
- Sources disagree on the run loop count: two or three
Race
How racers feel about it, how well it is run, and how it treats a first timer. Counts for 27% of the overall score.
- Racer satisfactionLiked3.4
No first-person reports found. Official sources are upbeat, with a record 1,500 athletes from 66 countries and regions, but that is press material. · Low confidence
- OrganizationWell run3.7
Organisers added aid stations, medical staff, parking and upgraded timing for 2026, and the 2025 winner praised the many aid stations. · Low confidence
- First timer friendlyFriendly3.7
Flat course and lake swim, though humid May heat and travel to China add friction. · Low confidence
Course traits, not part of the score
- PR potentialFast4.2
Max Studer won in 3:38:03 in 2025 on a flat two-loop out-and-back bike and a flat run. · Medium confidence
- Course easeModerate3.7
Flat course in warm, humid conditions. · Low confidence
Swim
Wetsuit odds, water temperature, calm, and the experience of the start. Counts for 15% of the overall score.
- Wetsuit legalCoin flip3.2
Water of about 21 °C (70 °F) would normally be legal, but the 2026 winner reported no wetsuit, so legality varies. · Low confidence
- Water temperatureComfortable4.3
21 °C (70 °F) average is within the ideal range. · Low confidence
- Calm waterMostly calm3.9
A 179 ha (442 acre) lake could get wind chop. No reports found. · Low confidence
- Swim easeEasy4.2
Single loop in a lake with a rolling self-seeded start. · Low confidence
- Swim experienceFine3.4
Ecological lake with water-quality standards stressed by organisers, but no athlete comments. · Low confidence
Bike
Road surface, closures, scenery and wind. Counts for 19% of the overall score.
- Road surfaceGood3.7
Organisers say roads were improved for 2026. · Low confidence
- Road closuresMostly closed3.9
A scenic-area highway is used. Closure details not documented. · Low confidence
- Bike sceneryPleasant3.0
Countryside, farmland and a long highway. · Low confidence
- WindSome wind2.8
Exposed flat estuary island, so wind is likely a factor. No reports. · Low confidence
Course traits, not part of the score
- Bike speedFast4.2
Two flat 45 km (28 mi) out-and-back loops on one highway, with a 3:38 winning finish. · Medium confidence
- Bike flatnessPancake flat4.6
Flat island road. Gain unpublished. · Low confidence
- Bike simplicityMostly simple4.4
Out-and-back with U-turns on one highway, very simple. · Medium confidence
Run
Crowds, aid stations, conditions underfoot and scenery. Counts for 13% of the overall score.
- Crowd supportDecent2.7
Rural island venue with no crowd reports. · Low confidence
- Aid stationsGood4.0
More aid stations were added for 2026 and the 2025 winner praised them. · Low confidence
- Run sceneryBeautiful3.6
Lakes, meadows and flower fields according to organisers. · Low confidence
- Run conditionsModerate3.3
The 2025 winner called the run quite warm. May highs reach 25 to 31 °C (77 to 88 °F) with humidity. · Low confidence
Course traits, not part of the score
- Run flatnessFlat4.7
Flat lake loop according to RaceRaves. · Medium confidence
Conditions
Air temperature, how predictable the weather is, setting, and spectating. Counts for 15% of the overall score.
- Air temperaturePleasant3.8
Lows of 15 to 20 °C (59 to 68 °F) and highs of 25 to 31 °C (77 to 88 °F), with humidity. · Low confidence
- Weather reliabilityVariable3.3
May in the Yangtze delta is unsettled. No cancellation history found. · Low confidence
- Venue beautyLovely3.5
Lakeside park with a wetlands feel. · Low confidence
- Spectator friendlySome viewpoints2.8
Remote island. Loops are repeated but the venue is far from town. · Low confidence
Course traits, not part of the score
- Low altitudeSea level5.0
Sea-level delta island. · High confidence
Stay and travel
Hotels, walkability, getting there, and the town around the race. Counts for 11% of the overall score.
- Hotel availabilityBook early3.4
Listings point to Shanghai city rather than the island. · Low confidence
- Hotel valueGood3.5
No pricing found. · Low confidence
- WalkabilitySome driving2.8
Most athletes stay off the island and travel in. · Low confidence
- Travel easeOne connection3.0
International hub at Pudong, but a long transfer onto the island. · Low confidence
- LogisticsSome complexity3.4
The lake venue serves swim and run, and the bike is on a nearby highway. · Low confidence
- Town and foodGood3.6
Shanghai is close for before and after the race, but the island itself is quiet. · Low confidence
Key facts
- Location
- Chongming Island (Bright Tian Yuan, Mingzhu Lake Park), Shanghai, China
- Typical month
- May
- Latest or next date
- 17 May 2026
- Organiser
- IRONMAN
- Field size
- About 1,500 athletes
- Distances
- 1.9 km (1.2 mi) swim, 90 km (56 mi) bike, 21.1 km (13.1 mi) run
- Swim venue
- Bright Tian Yuan lake (179 ha / 442 acres, Class II surface-water quality per organisers) (lake)
- Water temperature
- 21 °C (70 °F)
- Swim start
- rolling (self-seeded) from floating platform
- Swim laps
- 1
- Bike laps
- 2
- Run laps
- 2
- Run shade
- One description mentions plenty of shade; 2025 winner called the run quite warm
- Air temperature
- 15–31 °C (59–88 °F)
- Humidity
- humid (Yangtze delta)
- Altitude
- 3 m (10 ft)
- Nearest airport
- Shanghai Pudong (PVG) / Hongqiao (SHA)
- Where to stay
- Shanghai city, Chongming Island
- Booking
- Race listing offers accommodation in Shanghai city, not on the island.
What racers and reviewers say
- Tri247 2026 results reportRaced 2026 · article · Positive
Race report: Rongheng Chen won in 3:47:22 and Alanis Siffert in 4:05:30. Chen mentioned racing without a wetsuit, making the swim a little slower.
- Tri247 2025 results reportRaced 2025 · article · Positive
Studer won in 3:38:03 and Van Der Kaay in 4:06:10 on her 70.3 debut. Studer found the run warm and said the many aid stations helped him extend his lead.
- Shanghai government 2026 previewRaced 2026 · article · Positive
Upgrades for 2026: stricter lake water standards, improved Beiyan Highway roads and signage, more aid stations and medical staff, about 1,500 athletes from 66 countries and regions.
- RaceRaves race pageRaced 2026 · aggregator · Mixed
Course facts: self-seeded lake swim at 21 C (70 F), two 22.5 km (14 mi) out-and-back bike loops, flat two-loop run; May highs 25-31 C (77-88 F). No athlete reviews yet.
- WeRun listingRaced 2026 · aggregator · Positive
Calls the bike two-loop 'flat and fast' and the run fast; 4th edition, 7:40 am start on 17 May 2026.
Sources
Pages we used for facts and ratings. See how we rate.
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