Caitriona Jennings Sets Women's 100-Mile Record

In Vienna, Illinois, on November 8, 2025, Irish ultrarunner Caitriona Jennings set a new women's world record for the 100-mile distance, completing the Tunnel Hill 100 in 12 hours, 37 minutes and 4 seconds on her debut at the event.

The 45-year-old from Donegal shattered the previous mark of 12:42:40, established by American Camille Herron on the same course in 2017. Jennings finished fourth overall, nearly four hours ahead of the next woman, while averaging 7 minutes and 34 seconds per mile across the 160.9-kilometer route. The race, held on the flat Tunnel Hill State Trail—a crushed gravel path on a former railroad grade—features two 50-mile out-and-back loops and has a history of producing fast times since its inception.

Jennings, a former triathlete and 2012 Olympic marathoner for Ireland, approached the distance as a fresh challenge after a decade of success in shorter ultras. She holds Irish national records in the 50k (3:16:33) and 100k (7:43:01) and has earned multiple top-10 finishes at South Africa's Comrades Marathon, an 87-kilometer event. Her marathon personal best of 2:36:17 came in Rotterdam earlier that Olympic year, though she finished the London Games in...