The 2026 IRONMAN 70.3 World Championship is a 1.2 mile swim in the Mediterranean, a 56 mile bike through the Alpes-Maritimes hinterland, and a 13.1 mile run along the Promenade des Anglais in Nice, France. Here's your course breakdown and Best Bike Split race plan for race day.
If you're heading to Nice for the 2026 IRONMAN 70.3 World Championship, you've already done the hard part just to be on the start line. This isn't a race full of mass entries and open registration. Every athlete here qualified for it, which means the pace off the swim is fast from gun to finish. The bike course front loads nearly all of its climbing into the first 44 kilometers, then hands you 46 flat kilometers back into town before you run a shadeless out and back loop twice along the coast. Get the climbing wrong and the run tells on you fast.
Race Overview
The IRONMAN 70.3 World Championship has been crowning half distance champions since 2006, when the race began in Clearwater, Florida. It moved to Lake Las Vegas in 2011, then began rotating to a new host city most years starting in 2014. Nice has hosted the event once before, in 2019, when Gustav Iden and Daniela Ryf took the titles on the same roads racers will use in 2026. The city has also hosted the full distance IRONMAN World Championship for men in both 2023 and 2024, and with 2026 and a return trip in 2028 already on the calendar, Nice is set to become the second most frequent host of an IRONMAN world championship event, trailing only Kailua-Kona.
For 2026, the race splits across two days, with the women's field racing Saturday, September 12 and the men's field racing Sunday, September 13. Qualification for this race runs through the 70.3 series over the prior season, and the professional fields alone include 87 women and 89 men who earned their way onto the start list, racing alongside thousands of age group qualifiers who did the same. Unlike a typical 70.3, there's no walk up entry here. Everyone on that beach start earned their spot.
Course Description
The swim starts and finishes on the pebble beaches of the Baie des Anges, Nice's stretch of Mediterranean coastline. Sea temperatures in mid September typically sit right around the wetsuit legal threshold, so plan on packing both a wetsuit and a swimskin and deciding closer to race morning. Open water chop is a real possibility if the wind picks up, and the low morning sun over the water makes sighting harder than it looks on a calm day.
Out of transition, the bike heads inland and starts climbing almost immediately. Around 10 kilometers in, a sharp ramp through St-Laurent-du-Var hits grades near 13 percent, some of the steepest pitches you'll find on any IRONMAN branded course, road or gravel. That's just the appetizer. From kilometer 26.6 to 36.3, the route tackles the Col de Vence, 9.7 kilometers averaging 6.6 percent with stretches pushing past 10 and peaks over 12. This climb is where the race gets decided for most age groupers, not because it's the steepest thing they'll ever ride, but because it comes early enough to tempt riders into spending more than they have. A short bump through Coursegoules near kilometer 42 adds one more test before the terrain flips. Two technical descents follow, a tighter one around kilometer 47 to 49 with four hairpins, then an 11 kilometer drop from around kilometer 64 back toward Nice that demands full attention on tired arms. After kilometer 44, the course gains less than 90 meters of elevation over the remaining 46 kilometers, a long, fast, flat run back to transition.
The run is two out and back loops along the Promenade des Anglais, 21.1 kilometers total, flat the entire way with almost no shade off the water. Athletes run right past the finish line arch on the way into loop two, which catches more than a few first timers off guard mentally. There's nothing technical about this run course. It's simply a test of how much you left on the bike.
Forecasted Weather
Mid September in Nice runs warm and mostly dry, with daytime highs typically near 77 degrees and mornings closer to 64. Sea temperatures average around 72 to 73 degrees, close enough to the wetsuit legal cutoff that it's worth checking the final call in race week rather than assuming either way. The month sees roughly eight days of measurable rain, so a dry race is the more likely outcome, but coastal weather here can shift with wind off the water. With minimal shade on both the bike's flat closing miles and the entire run course, heat management matters even at what looks like a mild forecast on paper.
Why This Course Rewards a Best Bike Split Plan
Nice is often described as a bike course that decides the race by kilometer 40, and that's exactly why pacing the climb matters more than pacing almost anything else in triathlon. A BBS race plan for the 2026 IRONMAN 70.3 World Championship will:
- Set your target for the Col de Vence before you ever see it. This is the race's defining climb, and the athletes who blow up on the run almost always overcooked this section trying to match a rider who simply has a bigger engine. A number set ahead of time keeps you honest when the adrenaline says otherwise.
- Give the St-Laurent-du-Var ramp its own ceiling. It shows up just 10 kilometers into the bike, while the field is still sorting itself out of transition. Riders who treat it like a normal opening effort instead of the steep pitch it actually is start the day already in the red.
- Account for the run you still have to complete. This is a half distance triathlon, not a time trial. A plan built for Nice balances what the bike course allows against what you'll need in reserve for 13.1 flat, shadeless miles along the coast.
- Set a realistic number for the closing flat miles. After kilometer 44 the terrain goes fast and mostly flat all the way to transition, and it's tempting to hammer there once the climbing is behind you. A plan that accounts for the technical descents beforehand keeps you from arriving at that flat section already spent, and keeps you from spending too much of it anyway.
Interactive Race Plan and Course Map
This power plan was modeled for an athlete with an average CdA of 0.2388, an FTP of 350 watts and weighing 75 kg. Want to see what your time would be on the IRONMAN 70.3 World Championship Nice course? Try the Time Analysis feature below, where you can quickly adjust Drag, Power, Weight and Crr to your own values. Check out our demo race plan to see what a premium race plan looks like.
| Interval | Int. Time | Total Time | Int. Dist. | Total Dist. | Grade | Speed | Power |
|---|---|---|---|---|---|---|---|
| #1 | 00:09:47 | 00:09:47 | 6.90 km | 6.90 km | +0.07 % | 42.29 km/h | 250 w |
| #2 | 00:01:08 | 00:10:55 | 0.75 km | 7.65 km | -0.72 % | 39.67 km/h | 237 w |
| #3 | 00:00:21 | 00:11:17 | 0.21 km | 7.86 km | +2.98 % | 34.94 km/h | 300 w |
| #4 | 00:03:24 | 00:14:41 | 2.13 km | 9.99 km | +0.40 % | 37.59 km/h | 261 w |
| #5 | 00:02:26 | 00:17:08 | 0.64 km | 10.63 km | +9.37 % | 15.62 km/h | 323 w |
| #6 | 00:00:18 | 00:17:26 | 0.15 km | 10.78 km | -1.89 % | 29.91 km/h | 219 w |
| #7 | 00:01:14 | 00:18:40 | 0.32 km | 11.10 km | +9.35 % | 15.45 km/h | 327 w |
| #8 | 00:00:11 | 00:18:52 | 0.11 km | 11.21 km | -7.77 % | 32.36 km/h | 0 w |
| #9 | 00:00:46 | 00:19:39 | 0.50 km | 11.71 km | +0.78 % | 39.22 km/h | 268 w |
| #10 | 00:00:18 | 00:19:57 | 0.11 km | 11.82 km | +7.48 % | 22.67 km/h | 325 w |
| #11 | 00:00:22 | 00:20:19 | 0.24 km | 12.06 km | -6.73 % | 39.16 km/h | 81 w |
| #12 | 00:00:04 | 00:20:23 | 0.07 km | 12.13 km | -2.69 % | 54.32 km/h | 209 w |
| #13 | 00:01:13 | 00:21:37 | 0.46 km | 12.59 km | +6.81 % | 22.50 km/h | 321 w |
| #14 | 00:00:45 | 00:22:22 | 0.34 km | 12.93 km | +2.18 % | 26.93 km/h | 287 w |
| #15 | 00:00:10 | 00:22:32 | 0.07 km | 13.00 km | +5.64 % | 25.82 km/h | 316 w |
| #16 | 00:00:07 | 00:22:40 | 0.05 km | 13.05 km | -0.09 % | 24.30 km/h | 251 w |
| #17 | 00:00:10 | 00:22:51 | 0.09 km | 13.14 km | +1.94 % | 29.28 km/h | 286 w |
| #18 | 00:00:06 | 00:22:58 | 0.06 km | 13.20 km | +3.12 % | 29.42 km/h | 305 w |
| #19 | 00:00:20 | 00:23:18 | 0.22 km | 13.42 km | -2.49 % | 38.31 km/h | 207 w |
| #20 | 00:01:13 | 00:24:31 | 0.61 km | 14.03 km | +3.41 % | 29.84 km/h | 302 w |
| #21 | 00:00:33 | 00:25:05 | 0.33 km | 14.36 km | -0.27 % | 35.36 km/h | 247 w |
| #22 | 00:00:10 | 00:25:15 | 0.11 km | 14.47 km | +1.77 % | 37.63 km/h | 281 w |
| #23 | 00:00:36 | 00:25:51 | 0.14 km | 14.61 km | +12.56 % | 13.72 km/h | 339 w |
| #24 | 00:02:27 | 00:28:18 | 1.02 km | 15.63 km | +4.75 % | 24.90 km/h | 353 w |
| #25 | 00:04:23 | 00:32:42 | 1.80 km | 17.43 km | +3.85 % | 24.56 km/h | 301 w |
| #26 | 00:00:27 | 00:33:10 | 0.29 km | 17.72 km | -0.39 % | 37.90 km/h | 244 w |
| #27 | 00:01:15 | 00:34:25 | 0.71 km | 18.43 km | +1.79 % | 33.81 km/h | 284 w |
| #28 | 00:00:44 | 00:35:10 | 0.34 km | 18.77 km | +4.84 % | 27.48 km/h | 376 w |
| #29 | 00:00:45 | 00:35:55 | 0.40 km | 19.17 km | +1.44 % | 31.87 km/h | 279 w |
| #30 | 00:00:49 | 00:36:45 | 0.41 km | 19.58 km | +2.86 % | 29.86 km/h | 298 w |
| #31 | 00:01:17 | 00:38:02 | 0.96 km | 20.54 km | -1.74 % | 44.94 km/h | 222 w |
| #32 | 00:00:06 | 00:38:08 | 0.08 km | 20.62 km | +4.30 % | 43.82 km/h | 341 w |
| #33 | 00:07:03 | 00:45:12 | 4.45 km | 25.07 km | +0.80 % | 37.85 km/h | 266 w |
| #34 | 00:00:10 | 00:45:23 | 0.11 km | 25.18 km | -0.54 % | 36.53 km/h | 236 w |
| #35 | 00:01:25 | 00:46:48 | 1.13 km | 26.31 km | -1.70 % | 47.77 km/h | 219 w |
| #36 | 00:00:25 | 00:47:14 | 0.29 km | 26.60 km | +0.63 % | 40.94 km/h | 258 w |
| #37 | 00:05:38 | 00:52:52 | 1.84 km | 28.44 km | +6.24 % | 19.54 km/h | 321 w |
| #38 | 00:01:24 | 00:54:17 | 0.58 km | 29.02 km | +4.43 % | 24.55 km/h | 347 w |
| #39 | 00:00:08 | 00:54:26 | 0.06 km | 29.08 km | +2.97 % | 26.53 km/h | 298 w |
| #40 | 00:06:53 | 01:01:19 | 1.94 km | 31.02 km | +7.41 % | 16.89 km/h | 324 w |
| #41 | 00:17:52 | 01:19:12 | 5.30 km | 36.32 km | +6.71 % | 17.78 km/h | 322 w |
| #42 | 00:00:35 | 01:19:48 | 0.38 km | 36.70 km | -2.39 % | 38.43 km/h | 208 w |
| #43 | 00:00:21 | 01:20:10 | 0.35 km | 37.05 km | -4.94 % | 57.41 km/h | 170 w |
| #44 | 00:00:04 | 01:20:14 | 0.08 km | 37.13 km | -6.84 % | 64.28 km/h | 0 w |
| #45 | 00:00:18 | 01:20:32 | 0.29 km | 37.42 km | -1.85 % | 57.83 km/h | 220 w |
| #46 | 00:02:33 | 01:23:06 | 1.95 km | 39.37 km | -0.47 % | 45.59 km/h | 243 w |
| #47 | 00:01:05 | 01:24:11 | 0.63 km | 40.00 km | +1.79 % | 34.90 km/h | 288 w |
| #48 | 00:03:18 | 01:27:30 | 2.05 km | 42.05 km | +0.82 % | 37.13 km/h | 267 w |
| #49 | 00:00:07 | 01:27:38 | 0.09 km | 42.14 km | -0.40 % | 38.57 km/h | 247 w |
| #50 | 00:02:45 | 01:30:23 | 0.95 km | 43.09 km | +6.19 % | 20.65 km/h | 322 w |
| #51 | 00:01:18 | 01:31:42 | 0.82 km | 43.91 km | +0.71 % | 37.59 km/h | 261 w |
| #52 | 00:00:50 | 01:32:33 | 0.50 km | 44.41 km | +2.53 % | 35.26 km/h | 295 w |
| #53 | 00:01:46 | 01:34:19 | 1.77 km | 46.18 km | -3.38 % | 59.85 km/h | 184 w |
| #54 | 00:00:21 | 01:34:41 | 0.36 km | 46.54 km | -0.94 % | 60.04 km/h | 229 w |
| #55 | 00:00:52 | 01:35:34 | 0.87 km | 47.41 km | -4.51 % | 58.91 km/h | 172 w |
| #56 | 00:00:29 | 01:36:03 | 0.35 km | 47.76 km | -4.89 % | 42.78 km/h | 130 w |
| #57 | 00:00:09 | 01:36:13 | 0.10 km | 47.86 km | -6.63 % | 38.72 km/h | 0 w |
| #58 | 00:00:06 | 01:36:19 | 0.10 km | 47.96 km | -5.02 % | 55.54 km/h | 85 w |
| #59 | 00:02:45 | 01:39:04 | 2.69 km | 50.65 km | -4.62 % | 58.55 km/h | 173 w |
| #60 | 00:00:09 | 01:39:14 | 0.12 km | 50.77 km | -2.29 % | 44.04 km/h | 214 w |
| #61 | 00:00:49 | 01:40:04 | 0.56 km | 51.33 km | -0.35 % | 40.89 km/h | 244 w |
| #62 | 00:01:12 | 01:41:17 | 1.26 km | 52.59 km | -4.36 % | 62.40 km/h | 175 w |
| #63 | 00:00:03 | 01:41:20 | 0.06 km | 52.65 km | -6.25 % | 66.67 km/h | 0 w |
| #64 | 00:01:19 | 01:42:39 | 1.42 km | 54.07 km | -3.81 % | 64.41 km/h | 185 w |
| #65 | 00:00:03 | 01:42:43 | 0.07 km | 54.14 km | -12.76 % | 68.60 km/h | 0 w |
| #66 | 00:00:18 | 01:43:01 | 0.27 km | 54.41 km | -0.94 % | 53.68 km/h | 235 w |
| #67 | 00:00:38 | 01:43:40 | 0.60 km | 55.01 km | -6.63 % | 56.46 km/h | 0 w |
| #68 | 00:00:04 | 01:43:45 | 0.09 km | 55.10 km | -4.07 % | 71.57 km/h | 174 w |
| #69 | 00:00:45 | 01:44:30 | 0.89 km | 55.99 km | -5.98 % | 71.36 km/h | 0 w |
| #70 | 00:00:38 | 01:45:08 | 0.50 km | 56.49 km | -3.46 % | 47.41 km/h | 188 w |
| #71 | 00:00:51 | 01:45:59 | 0.77 km | 57.26 km | -1.59 % | 54.15 km/h | 218 w |
| #72 | 00:03:53 | 01:49:53 | 2.05 km | 59.31 km | +2.78 % | 31.71 km/h | 297 w |
| #73 | 00:00:23 | 01:50:16 | 0.23 km | 59.54 km | +0.49 % | 35.20 km/h | 259 w |
| #74 | 00:00:28 | 01:50:44 | 0.34 km | 59.88 km | -0.70 % | 42.86 km/h | 235 w |
| #75 | 00:01:48 | 01:52:32 | 1.66 km | 61.54 km | -4.22 % | 55.03 km/h | 177 w |
| #76 | 00:00:12 | 01:52:44 | 0.23 km | 61.77 km | -7.90 % | 68.43 km/h | 0 w |
| #77 | 00:00:02 | 01:52:47 | 0.05 km | 61.82 km | -4.92 % | 72.42 km/h | 130 w |
| #78 | 00:00:02 | 01:52:50 | 0.06 km | 61.88 km | +1.03 % | 68.48 km/h | 267 w |
| #79 | 00:00:26 | 01:53:16 | 0.32 km | 62.20 km | -2.00 % | 44.63 km/h | 208 w |
| #80 | 00:00:17 | 01:53:33 | 0.25 km | 62.45 km | -4.23 % | 52.06 km/h | 174 w |
| #81 | 00:01:44 | 01:55:17 | 1.42 km | 63.87 km | -1.15 % | 49.13 km/h | 231 w |
| #82 | 00:01:15 | 01:56:33 | 0.98 km | 64.85 km | -3.40 % | 46.71 km/h | 188 w |
| #83 | 00:00:23 | 01:56:56 | 0.28 km | 65.13 km | -5.66 % | 43.17 km/h | 30 w |
| #84 | 00:00:33 | 01:57:29 | 0.52 km | 65.65 km | -4.11 % | 56.56 km/h | 180 w |
| #85 | 00:00:19 | 01:57:49 | 0.37 km | 66.02 km | -6.09 % | 67.78 km/h | 0 w |
| #86 | 00:06:23 | 02:04:13 | 5.13 km | 71.15 km | -1.57 % | 48.18 km/h | 217 w |
| #87 | 00:00:22 | 02:04:35 | 0.32 km | 71.47 km | -4.33 % | 50.90 km/h | 175 w |
| #88 | 00:01:07 | 02:05:42 | 1.11 km | 72.58 km | -5.05 % | 59.89 km/h | 139 w |
| #89 | 00:03:08 | 02:08:51 | 3.03 km | 75.61 km | -4.89 % | 57.83 km/h | 166 w |
| #90 | 00:04:09 | 02:13:00 | 3.35 km | 78.96 km | -0.39 % | 48.36 km/h | 240 w |
| #91 | 00:00:04 | 02:13:05 | 0.06 km | 79.02 km | +0.85 % | 44.42 km/h | 264 w |
| #92 | 00:00:31 | 02:13:36 | 0.38 km | 79.40 km | -2.17 % | 43.46 km/h | 207 w |
| #93 | 00:02:12 | 02:15:49 | 1.67 km | 81.07 km | -0.47 % | 45.29 km/h | 238 w |
| #94 | 00:00:07 | 02:15:56 | 0.10 km | 81.17 km | -3.18 % | 49.81 km/h | 191 w |
| #95 | 00:02:55 | 02:18:51 | 2.20 km | 83.37 km | +0.02 % | 45.22 km/h | 246 w |
| #96 | 00:00:20 | 02:19:12 | 0.28 km | 83.65 km | -2.38 % | 49.60 km/h | 200 w |
| #97 | 00:00:52 | 02:20:04 | 0.56 km | 84.21 km | +1.05 % | 38.33 km/h | 270 w |
| #98 | 00:10:59 | 02:31:03 | 7.62 km | 91.83 km | -0.07 % | 41.60 km/h | 251 w |
| #99 | 00:00:33 | 02:31:37 | 0.34 km | 92.17 km | +2.26 % | 36.08 km/h | 290 w |
| #100 | 00:01:32 | 02:33:09 | 1.02 km | 93.19 km | -1.33 % | 40.01 km/h | 228 w |
| Totals/Avg | 02:33:09 | 02:33:09 | 93.22 km | 93.22 km | -0.55% | 36.52 km/h | 259.80 w |
Climb Summary by Category
| Category | Climb Count | Total Time | Total Dist. | Avg. Time | Avg. Dist. | Avg. Grade | Avg. Speed | Avg. Power |
|---|---|---|---|---|---|---|---|---|
| Cat2 | 1 | 00:31:58 | 9.72 km | 00:31:58 | 9.72 km | 6.51 % | 18.24 km/h | 322 w |
| Cat4 | 5 | 00:22:29 | 9.28 km | 00:04:29 | 1.86 km | 4.10 % | 25.47 km/h | 311 w |
| All Cats | 6 | 00:54:27 | 19.00 km | 00:09:04 | 3.17 km | 4.50 % | 24.26 km/h | 313 w |
| Climb | Start Time | Start Dist. | Duration | Distance | Speed | Power | Grade | Elevation Gain | Category |
|---|---|---|---|---|---|---|---|---|---|
| #1 | 00:14:41 | 10.00 km | 00:05:15 | 1.83 km | 20.92 km/h | 274 w | 4.62 % | 84.63 m | Cat4 |
| #2 | 00:20:23 | 12.14 km | 00:04:07 | 1.89 km | 27.46 km/h | 289 w | 3.21 % | 60.71 m | Cat4 |
| #3 | 00:25:15 | 14.47 km | 00:07:27 | 2.95 km | 23.79 km/h | 322 w | 4.41 % | 130.15 m | Cat4 |
| #4 | 00:34:25 | 18.42 km | 00:00:44 | 0.34 km | 27.48 km/h | 376 w | 4.84 % | 16.32 m | Cat4 |
| #5 | 00:47:14 | 26.60 km | 00:31:58 | 9.72 km | 18.24 km/h | 322 w | 6.51 % | 632.99 m | Cat2 |
| #6 | 01:27:38 | 42.14 km | 00:04:54 | 2.27 km | 27.69 km/h | 295 w | 3.40 % | 77.26 m | Cat4 |
Build your own personalized IRONMAN 70.3 World Championships power plan today! Sign up for a free Athlete Basic account to get started with your athlete profile and bike setup, then grab the IRONMAN 70.3 World Championship Nice course to model your own race plan.
IRONMAN 70.3 World Championships FAQs
Your target power depends on your FTP, body weight, bike setup, and finish time goal — not a generic number that applies to every rider. The variables that matter most are your current fitness, your aerodynamic position, and the specific demands of the IRONMAN 70.3 World Championships course. The best approach is to build a personalized plan in Best Bike Split using your actual athlete profile — you'll get a segment-by-segment power target based on your specific inputs rather than a one-size-fits-all recommendation.
Every course is different and requires its own unique pacing plan. On a multi-loop course, fatigue and wind shift between laps and what felt comfortable early can become unsustainable later. On an out-and-back, headwind in one direction becomes tailwind in the other — an asymmetry a flat power target can't account for. On a point-to-point or single-loop course, you only get one pass at every section with no opportunity to recalibrate. When you create a Best Bike Split race plan for IRONMAN 70.3 World Championships, we model the specific demands of that course so your pacing strategy reflects the race you're actually doing.
Significantly — and the effect varies depending on the course profile. On flatter courses, wind and aerodynamics become the dominant variables in your speed equation, more so than on courses where gradient naturally dictates effort. On climbing-heavy courses, your power-to-weight ratio and how you manage the descents matter most. A Best Bike Split race plan lets you model the specific conditions forecasted for IRONMAN 70.3 World Championships, so your targets reflect what you'll actually face on race day rather than what the course looks like on paper.
It depends on the course and how well you pace it. Flat, fast courses offer genuine PR potential but only if you execute correctly — without terrain to naturally regulate your effort, going out too hard early is easy and costly. Technical or hilly courses reward smart segment-by-segment pacing over raw fitness. Either way, a physics-based race plan from Best Bike Split gives you a realistic split prediction based on your actual profile so you know before race day what a well-executed bike leg looks like for you specifically.
Yes — and this is one of the most underused features. Once you've built your IRONMAN 70.3 World Championships race plan, you can export it directly to Zwift, TrainerRoad, or any ERG-mode trainer for indoor sessions, or push it to your Garmin, Wahoo, or Karoo for outdoor rides. Training on your actual race plan means you arrive at IRONMAN 70.3 World Championships already knowing what your target effort feels like at every section of the course — not just what the number says on paper.
