16-year-old Estes Park high school student Ellie Kostadinov has beaten the fastest women in the “Under 19” Category for mountain biking Utah’s iconic White Rim Trail for the second year in a row. Kostadinov beat her own record from 2024, which was challenged, but not bested, by other riders in the category during 2025. Kostadinov set the new record on October 25, 2025 with a time of 7 hours, 55 minutes and 36 seconds.
The 100-mile course, located in scenic Canyonlands National Park, is an athletic test-piece for mountain bike enthusiasts. Completing the challenge “in a day,” is a popular contest, with world-class professional riders flocking to the region each spring and fall to try to gain the fastest known time. Overall winners are Keegan Swenson, who clocked a blazing time of 5:28:17 in March of 2021 when he was 27 years old, and Hanna Otto, who set a record of 6:36:51 in May of 2025 at the age of 29.
Kostadinov plans to attempt the ride in the autumn of 2026 when she will be 17 years old to lower her time even more. “If I can complete the White Rim in under seven hours this fall, I will be happy,” the teenager said. This lofty goal would place her among the top three women who have been able to complete the course in under seven hours, and would put her within 30 minutes of Otto’s all-time women’s record…