The Annual Waikīkī Roughwater Swim returns on Monday, September 1, 2025, with an 8:30 a.m. start at Kaimana (Sans Souci) Beach and a point-to-point course across Waikīkī to Duke Kahanamoku Beach, continuing a Labor Day tradition that began in 1970. Online registration opens April 2 and remains available through August 30, with tiered entry fees and limited in-person and race-day registration the day before and the morning of the event in Waikīkī. This 54th edition covers 2.384 miles (3.84 km), requires the official race cap, and enforces simple, fair suit rules that keep the focus on pure open-water swimming in the warm, clear waters off O‘ahu’s south shore.
Date, time, place
- Race date and time: Monday, September 1, 2025; start 8:30 a.m. HST, check-in from 7:00 a.m. per local listings; online registration closes at midnight HST August 30.
- Start: Sans Souci (Kaimana) Beach, between the Waikīkī Natatorium and the Kaimana Beach Hotel at the base of Lē‘ahi (Diamond Head).
- Finish: Duke Kahanamoku Beach fronting Hilton Hawaiian Village, with the official finishing line up the beach beyond the water’s edge.
Distance, course, and format
- Course length: 2.384 miles / 3.84 kilometers, swum point-to-point across Waikīkī Bay, typically out through Kapua Channel and north along the bay to the Hilton channel at the finish.
- Format: Seeded wave starts by estimated time to reduce congestion; safety flotilla of lifeguards, paddlers, and boats patrols the course. Swimmers who do not pass designated buoys or cutoffs may be pulled for safety per the race committee.
- Time limit: Historical guidance states a cutoff around 2 hours 40 minutes; swimmers must cross the land-based finish line to record an official time.
Registration, fees, and what’s included
- Registration windows and pricing:
- Through June 16: $80 (online).
- June 17–August 9: $90 (online).
- August 10–August 30: $100 (online; closes midnight HST Aug 30).
- August 31: $115 (in-person late reg).
- September 1: $125 (race-day entry, limited availability).
- Entry includes: Official WRS swim cap and event shirt (tank option for early entries before 8/11 as noted by the organizer’s feed).
- Where to register: Event site registration portal and Finish Line Productions listing for the 54th Annual Waikīkī Roughwater Swim.
Suit, gear, and conduct rules
- Mandatory cap: The official WRS color cap must be worn throughout; body marking is required and must remain visible.
- Suits: Men may wear briefs, box/square cuts, or jammers; women may wear one- or two-piece suits from shoulder to hip without shoulder coverage. No tri suits, swim skins, buoyant fabrics, wetsuits, fins (except in a separate fin division), flotation devices, or any performance aids; penalties or disqualification apply for non-compliance.
- Escorts: No personal escorts (surfboards, kayaks, boats) permitted to ensure fair competition and clear safety lanes.
Tide, weather, and conditions
- Tide forecast (race listing): High tide near 7:52 a.m. (~1.88 ft) and low tide around 2:32 p.m., with sunrise at 6:15 a.m. on race day, typical for late-summer mornings in Waikīkī.
- Conditions: Expect warm water, tradewind chop, and variable currents near channels and reef edges; sighting landmarks and buoys is essential across the bay.
Start logistics and waves
- Check-in and numbering: Bring email confirmation; proceed to body marking and cap pickup (organizers email bib numbers near race weekend).
- Waves: Seeded groups of roughly 150–200 swimmers release in intervals to spread the field; faster entrants go earlier to reduce crowding and ensure clear safety oversight across the course.
- Cutoffs and pulls: Swimmers behind schedule at critical buoys may be removed for safety and transported to shore; safety is prioritized over finishing at all times.
Why this swim is iconic
- History and influence: A Labor Day staple since 1970, the Waikīkī Roughwater helped inspire the swim leg of the original Hawaiian Ironman triathlon and remains one of the world’s best-known ocean races, recognized in global open-water rankings and island swim lists.
- Setting: A route that begins under Diamond Head and finishes on Duke Kahanamoku’s namesake beach blends athletic challenge with the birthplace of modern surfing, giving the finish a uniquely Hawaiian resonance.
- Community: Hosted by the Waikiki Roughwater Swim Committee with support from the Waikiki Swim Club, the event attracts Olympians, elites, and first-timers, creating a shared field with real depth and welcoming spirit.
Training and race-day tips
- Prepare for sighting and chop: Practice bilateral breathing, sighting every 6–10 strokes, and steady pacing in wind chop; local conditions often mean small, frequent corrections across the bay.
- Practice channel entries: The start line at Sans Souci leads into Kapua Channel with reef edges and variable current; swim a rehearsal line in the days before if possible.
- Start strategy: Seed accurately to avoid mismatched packs; swimming clean water in a compatible wave group often saves time and stress compared with starting too far back.
- Nutrition: Eat a familiar, light breakfast 2–3 hours before; hydrate early. Race morning crowds make last-minute food runs tricky, so plan ahead.
- Gear check: Anti-chafe, tinted goggles for glare, and a backup pair; secure your timing and body marking per instructions. Minimal extra gear is best in warm, short-course ocean swims.
Spectator and logistics guide
- Best viewing: Sans Souci (Kaimana) Beach for the start energy and Duke Kahanamoku Beach for the run-up finish line; hotel lanais and the pier area near Hilton give elevated views during final approach.
- Parking and transit: Waikīkī street parking is tight; use hotel parking, rideshare, or walk from accommodations. Allow extra time for check-in, body marking, and wave calls.
- Post-race: Finishers exit past the line for refreshments and awards; meet family and friends well beyond the finish chute to relieve congestion.
After the finish: celebrate and recover
- Refuel: Waikīkī cafés near Kalia Road and the Hilton lagoon offer easy options for breakfast or early lunch; rehydrate and get shade soon after finishing.
- Active recovery: An easy lagoon float, short walk, or gentle stretch keeps muscles loose; avoid extended sun exposure right after a long saltwater swim.
- Extend the trip: Consider the Waikiki Double Roughwater Swim (scheduled Oct 4, 2025) or other Waikiki Swim Club ocean races if staying longer into fall.
Verified details at a glance
- Name: 54th Annual Waikīkī Roughwater Swim.
- Date: Monday, September 1, 2025 (Labor Day); start 8:30 a.m..
- Start/finish: Start at Kaimana (Sans Souci) Beach; finish at Duke Kahanamoku Beach by Hilton Hawaiian Village.
- Distance: 2.384 miles / 3.84 km; point-to-point across Waikīkī.
- Registration: Opens April 2; online through Aug 30; late reg Aug 31; limited race-day entry Sept 1.
- Fees: $80 (to Jun 16); $90 (to Aug 9); $100 (to Aug 30); $115 (Aug 31); $125 (Sept 1).
- Rules: Official WRS cap mandatory; fair-suit policy; no personal escorts; non-compliance may incur penalties or disqualification.
Set the alarm for a sunrise check-in, seed a wave that matches the pace, and let the trade winds and the Diamond Head skyline frame a storied swim. Secure a spot before online registration closes, review the course and suit rules, and plan an easy finish meet-up at Duke’s beach. On Labor Day 2025, join a field that has defined ocean swimming for more than half a century — and savor every stroke across Waikīkī’s blue.