Demand for ultramarathon trail races across the United States is rising, but the wilderness settings that make many events special also limit how many runners can take part. As a result, entry lotteries and qualifying races have become a defining part of the sport.
In 2016, 58,425 runners entered U.S. ultras. By 2025, the total had climbed above 100,000. Yet popular events have little room to expand: more than 11,000 runners sought 257 lottery places for the 2026 Western States Endurance Run, whose field is capped at 369 starters.
Protecting trails while managing demand
The Western States course crosses the Granite Chief Wilderness, where a long-standing agreement limits the number of starters. The Hardrock 100, which requires permits from several authorities, has room for 147 entrants. These limits help race organizers balance the event with the needs of protected landscapes and other trail users.
Entry systems vary. Western States applicants must complete a qualifying race of at least 100 kilometers, with additional lottery tickets awarded to those who qualify and apply in successive years. Hardrock uses separate lottery pools for previous finishers and those who have not completed the course. The Leadville 100 Trail Run also relies on a lottery, while its field is larger.
The growth of the sport is creating opportunities beyond these established races. Events such as Run, Rabbit, Run and longer-distance ultras are attracting runners seeking new challenges. Organizers are also discussing whether shared safety standards could help participants assess newer events, where remote terrain calls for careful planning and experienced support.
As trail running expands, the sport's next chapter will depend on making room for new participants while caring for the landscapes and communities that host each race.
