Seafair Triathlon
Seattle, United States · July · Independent (Seafair)
Why people love it
- Swim in a protected cove of Lake Washington, about 20 °C (68 °F), with lifeguards and small waves.
- A super sprint with a 0.4 km (0.25 mi) swim suits first-timers.
- Packet pickup the day before, then a one-lap run through shaded Seward Park.
- Sold out in 2026. Sprint only, with a 20 km (12.4 mi) bike.
Watch out for
- Seward Park is closed to participant parking. Park in the neighbourhood and cycle in.
- Transition opens at 05:30 and bikes cannot be racked the day before.
- The bike has one notable hill, and no elevation figure is published.
- Almost no first-person race reports exist. Most information is organiser or news listings.
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 satisfactionLoved3.6
It sold out in 2026 and draws about 1,500, but no athlete has written a first-person review. · Low confidence
- OrganizationWell run3.6
Logistics and timings are published clearly. There are no race-day reports of problems or praise. · Low confidence
- First timer friendlyFriendly4.0
A 0.4 km (0.25 mi) super sprint, small waves and lifeguards. · Low confidence
Course traits, not part of the score
- PR potentialFast3.5
One hill. The 2010 course record was 57:05. · Low confidence
Swim
Wetsuit odds, water temperature, calm, and the experience of the start. Counts for 16% of the overall score.
- Wetsuit legalUsually3.8
Lake averages about 20 °C (68 °F) in July. No rule is published, and USA Triathlon's limit is 25.6 °C (78 °F). · Low confidence
- Water temperatureComfortable4.1
About 20 °C (68 °F) in July per the organiser, in the comfortable range. · Low confidence
- Calm waterMostly calm3.8
Protected cove of Andrews Bay that the organiser calls calm. No race-day reports. · Low confidence
- Swim easeEasy3.8
Protected cove, one lap. · Low confidence
- Swim experienceGreat3.6
Lake swim in a park setting. Clarity is not described. · Low confidence
- Swim supportGood3.8
Lifeguards on site, small waves and a shallow kids' swim. Kayak numbers are not described. · Low confidence
Bike
Road surface, closures, scenery and wind. Counts for 18% of the overall score.
- Road surfaceMixed3.3
Surface is not described. · Low confidence
- Road closuresMostly closed3.5
Listings say closed roadway, but the extent of closure is unverified. · Low confidence
- Bike sceneryBeautiful3.9
Lake Washington Boulevard with lake views through Leschi and Madison Park. · Low confidence
- WindMostly calm3.7
Seattle summer mornings are usually calm. No race reports. · Low confidence
Course traits, not part of the score
- Bike speedFast3.5
Called fast by the organiser, with one hill. · Low confidence
- Bike flatnessMostly flat3.6
One hill per the organiser. Gain is probably 100 to 200 m (330 to 650 ft) over 20 km (12.4 mi). · Low confidence
- Bike simplicitySome technical parts3.3
City lake road with neighbourhood turns. Detail is not published. · Low confidence
Run
Crowds, aid stations, conditions underfoot and scenery. Counts for 13% of the overall score.
- Crowd supportDecent3.2
Park finish with families. No reports on crowds. · Low confidence
- Aid stationsStandard3.3
Aid is not described. · Low confidence
- Run sceneryBeautiful4.2
Forested Seward Park along the lake. · Low confidence
- Run conditionsEasy3.6
Shade and cool air. · Low confidence
Course traits, not part of the score
- Run flatnessRolling3.2
Upper-loop out-and-back in a hilly park. · Low confidence
Conditions
Air temperature, how predictable the weather is, setting, and spectating. Counts for 13% of the overall score.
- Air temperaturePleasant4.4
July mornings are typically about 13 to 24 °C (55 to 75 °F). · Low confidence
- Weather reliabilityReliable3.9
Seattle in July is usually dry. No cancellation reports. · Low confidence
- Venue beautyLovely4.1
Wooded peninsula park on Lake Washington. · Low confidence
- Spectator friendlyEasy3.6
Compact park with swim and finish close together, but the bike leaves the park. · Low confidence
Course traits, not part of the score
- Low altitudeSea level4.9
About 10 m (33 ft) above sea level. · High confidence
Stay and travel
Hotels, walkability, getting there, and the town around the race. Counts for 10% of the overall score.
- Hotel availabilityGood3.8
Seattle has many hotels, and this is mainly a local day-trip race. · Low confidence
- Hotel valueNormal3.0
Seattle summer rates are high. Nothing race-specific. · Low confidence
- WalkabilitySome driving2.9
Seward Park is closed to participant parking in 2026, so park in the neighbourhood and cycle in. · Medium confidence
- Travel easeEasy4.2
Sea-Tac airport is about 20 km (12 mi) away. · Medium confidence
- LogisticsSimple3.6
Saturday packet pickup, a single park venue and a 05:30 transition opening. Parking is the friction. · Low confidence
- Town and foodGood4.2
Seattle has strong dining, but the park itself has few amenities. · Low confidence
Key facts
- Location
- Seattle, Washington, United States
- Typical month
- July
- Latest or next date
- 19 July 2026
- Organiser
- Independent (Seafair)
- Field size
- About 1,500 athletes
- Entry fee
- About $105
- First held
- 2001
- Distances
- 0.8 km (0.5 mi) swim, 20 km (12.4 mi) bike, 5 km (3.1 mi) run
- Swim venue
- Andrews Bay, Seward Park, Lake Washington (lake)
- Water temperature
- 19–21 °C (66–70 °F)
- Wetsuit
- Optional
- Swim start
- wave
- Swim laps
- 1
- Key climbs
- One hill per organiser
- Run laps
- 1
- Run shade
- Forested Seward Park, much shade
- Air temperature
- 13–24 °C (55–75 °F)
- Humidity
- Low to moderate
- Altitude
- 10 m (33 ft)
- Nearest airport
- Seattle-Tacoma International (SEA), 20 km (12 mi) away
- Where to stay
- Seward Park neighbourhood, Columbia City, Downtown Seattle
- Booking
- Seward Park is closed to participant parking in 2026; organisers recommend parking in the neighbourhood and cycling in. Packet pickup Saturday 12:30 to 4:30 pm at the park; race-day pickup from 6 am; transition opens 5:30 am; bikes cannot be racked Saturday.
What racers and reviewers say
- Seafair official pageRaced 2026 · article · Positive
Organiser page for the 2026 race: sold out, triangular protected-cove swim, 20 km (12.4 mi) bike north along Lake Washington Blvd with one hill, a Seward Park run loop, Saturday packet pickup and 5:30 am transition. Marketing source, used for facts only.
- FOX 13 SeattleRaced 2025 · article · Positive
Race-week preview for the 2025 edition: 7 am to noon, half-mile (0.8 km) swim, 12.4 mi (20 km) bike, 5K run, and a quarter-mile (0.4 km) super sprint; advises biking or transit because neighbourhood parking is limited. Preview, not an athlete account.
- Seattle's ChildRaced 2025 · article · Positive
Family-events listing: flat, fast course along Lake Washington, small wave sizes, athletes from elite to first-timers, and kids' races with a shallow-water short swim. Listing copy, so promotional.
- Sequim GazetteRaced 2024 · article · Positive
Local sports brief: about 1,500 athletes on 21 July 2024 across sprint, super sprint, relay, kids and duathlon. A teen finisher placed fourth in 63 min 51 s, showing typical sprint times.
- Mercer Island ReporterRaced 2013 · article · Positive
Results story: the 2013 race had 311 Olympic finishers and 627 sprint finishers, showing it once ran both distances. No course comments.
Show 1 more
- HeraldNetRaced 2010 · article · Positive
Results story for the 10th edition (18 July 2010): half-mile swim, 12-mile bike and 3.1-mile run at Seward Park; winner set a course record of 57:05. No course commentary.
Raced Seafair Triathlon? Your notes on the course, conditions and logistics help the next athlete decide.
Sources
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