| 06 May 2023 |
Pen Llyn Ultra (50 Miles|75 Miles|100 Miles) |
Y Ffor, Wales, United Kingdom |
| 06 May 2023 |
Collegiate Peaks Trail Run (25 Miler|50 Miler) |
Buena Vista, Colorado, United States |
| 06 May 2023 |
Quad Rock 50 (50 Miler|25 Miler) |
Fort Collins, Colorado, United States |
| 07 May 2023 |
Tamworth All-Schools Mountain Bike Event (Primary All-Schools MTB Event|Secondary All-Schools MTB Event) |
Tamworth, New South Wales, Australia |
| 07 May 2023 |
Toronto Marathon (5K|Marathon|Half Marathon|10K) |
Toronto, Ontario, Canada |
| 07 May 2023 |
BMO Vancouver Marathon (Half Marathon|Marathon) |
Vancouver, British Columbia, Canada |
| 08 May 2023 |
Klipspringer Challenge (Klipspringer Lite Day One|Klipspringer Challenge Day One|Klipspringer Lite Day Two|Klipspringer Challenge Day Two) |
Augrabies, Northern Cape, South Africa |
| 12-14 May 2023 |
Ultra-Trail Snowdonia (30 Miles|50 Miles|100 Miles) |
Fachwen, Wales, United Kingdom |
| 12 May 2023 |
Thunderbunny Trail Races (25K|11K|50K) |
Athens, Ohio, United States |
| 12 May 2023 |
Hellbender 100 (Mens 100 Mile) |
Old Fort, North Carolina, United States |
| 13 May 2023 |
Devon Coast to Coast (117 Miles) |
South Hams, England, United Kingdom |
| 13 May - 12 Aug 2023 |
Swiss Alps 100 (Kids Run Mini and Rookies|Kids Run Youngsters|For Sportograf|virtual 400KM|virtual 800KM|Vertical|160KM|Course Directional Signs Map|50KM|100KM) |
Fiesch, Valais, Switzerland |
| 13 May 2023 |
Ultra-Trail Austrailia (50k|100k) |
Katoomba, New South Wales, Australia |
| 13 May 2023 |
PCT 50 (50 Miler) |
Cleveland National Forest, California, United States |
| 13 May 2023 |
Zegama-Aizkorri (Marathon) |
Zegama, Basque Country, Spain |
| 13 May 2023 |
Quicksilver (100K|50K) |
San Jose, California, United States |
| 13 May 2023 |
Ice Age Trail Endurance Runs (50k|Half Marathon|50 Miler) |
La Grange, Wisconsin, United States |
| 13 May 2023 |
Survival of the Fittest 18k (18k) |
Squamish, British Columbia, Canada |
| 13 May 2023 |
Ram Party (24K|33K|50 Mile|50K|5K|16K) |
Colorado Springs, Colorado, United States |
| 13 May 2023 |
Survival of the Fittest 35k (35k) |
Squamish, British Columbia, Canada |