Fastest Ironman 70.3 Bike Courses
Ranked by median finisher bike speed across the standard 90 km distance. Courses at the top are flat, smooth, and reward pure power output.
| # | Race | Region | Avg Speed | Median Bike Split | Median Total | Finishers | Estimate |
|---|---|---|---|---|---|---|---|
| 1 | Ironman 70.3 Knokke-Heist (2025) | Other | 32.8 km/h | 2:44:52 | 5:34:56 | 1,852 | |
| 2 | Ironman 70.3 Aracaju-Sergipe (2025) | Latin America | 31.6 km/h | 2:50:59 | 5:52:27 | 1,016 | |
| 3 | Ironman 70.3 Belgrade (2025) | Other | 31.5 km/h | 2:51:30 | 5:43:16 | 552 | |
| 4 | Ironman 70.3 Rio de Janeiro (2025) | Latin America | 30.8 km/h | 2:55:36 | 5:26:12 | 1,444 | |
| 5 | Ironman 70.3 Aix-en-Provence (2025) | Europe | 30.2 km/h | 2:58:58 | 5:43:44 | 2,214 | |
| 6 | Ironman 70.3 Augusta (2025) | North America | 29 km/h | 3:05:54 | 6:12:31 | 2,142 | |
| 7 | Ironman 70.3 Washington Tri-Cities (2025) | North America | 27.8 km/h | 3:14:06 | 5:58:54 | 1,634 | |
| 8 | Ironman 70.3 Acapulco (2025) | Latin America | 27.3 km/h | 3:17:34 | 6:28:56 | 346 | |
| 9 | Ironman 70.3 Hawaii (2025) | North America | 26.7 km/h | 3:22:20 | 6:50:27 | 873 |
9 races shown. Click any column header to re-sort.
Average bike speed is derived by dividing the standard Ironman 70.3 bike distance (90 km) by the median finisher bike split for that race. We use the median rather than the mean because elite professionals can distort average speeds on smaller fields. The median gives a truer picture of what a typical competitive age-grouper experiences on the course.
Higher km/h values indicate flatter terrain, better road surfaces, fewer technical turns, and often net-downhill or tailwind-assisted profiles. Lower values typically reflect significant elevation gain, technical cornering, or exposed coastal winds that affect the entire field uniformly.
Note that race-day weather — particularly headwinds and crosswinds — can shift a course's effective speed by 2–4 km/h year-to-year. Where multiple years of data are available, the most recent edition is used. If you are a strong cyclist, courses near the top of this list represent your best opportunity to bank time before the run.