Pocatello’s Brittany Peterson was part of a historic Western States 100-Mile Endurance Run this past weekend in California.

The 33-year-old finished second among women, 19th overall and clocked the fourth-fastest women’s time in race history (17 hours, 34 minutes, 29 seconds).

Peterson, first-place women’s finisher Clare Gallagher and third-place women’s finisher Kaci Lickteig all finished in under 18 hours, a Western States first.

The run, which was established in 1977 and takes place at the end of each June, is the world’s oldest 100-mile trail race, according to the event’s web site. It sends competitors from Squaw Valley, California, west to Auburn, California, on a course includes an elevation climb of more than 18,000 feet and a descent of more than 23,000 feet, according to the event’s web site.

Peterson was one of four Idahoans to qualify for the race, along with Twin Falls’ Drew Adams, Challis’ Celia Leber and Stanley’s Brian Westphal. Adams finished 48th, Westphal finished 255th and Leber did not finish. The race had 369 entrants.

Peterson and Gallagher ran together during the race’s late stages until Gallagher separated at around the 96.8-mile mark, according to Runner’s World. Gallagher’s winning time of 17:23:25 is the second-fastest women’s time in race history.

Arizona’s Jim Walmsley won the race for the second year in a row, shattering his own course record with a time of 14:09:28, according to Runner’s World.

Peterson qualified for the prestigious race by winning one of five Altra Golden Ticket races, which are held around the country from January through April. The top two men and top two women from each of the five golden ticket races gain entry into Western States, which accepts 369 qualifiers out of 5,800 lottery entrants, according to John Trent of Western States media relations.

Peterson won the Bandera 100K on Jan. 5 in Texas to automatically qualify, Trent said.