If you go

What: High school series race — Chalk Creek Ranch

When: Sunday; 10 a.m. start; registration begins at 8.

Where: Nathrop, Colo.

More info: coloradomtb.org

The kick-off race for the Colorado High School Cycling League’s inaugural season is Sunday, and with 120 racers registered, they could have a record-setting juniors field, said league director Kate Rau.

“I don’t know of any race where there’s been this many kids at one mountain-bike race” in Colorado, she said.

“Usually, 40 would be a lot,” she added.

The Colorado High School Mountain Bike Racing Series consists of four cross-country races across the state through October; the first, Sunday, is in Nathrop, south of Buena Vista. Racers will compete in varsity, junior varsity and freshman/sophomore divisions.

The state championship race will take place Oct. 31 in Elbert.

It’s the first series — and first season — for the league, which has high school students registered either as individuals or through school mountain-bike teams across Colorado and even southern Wyoming.

Locally, teams have formed at Boulder High School, Monarch, Fairview and Lyons, Rau said. Individual riders registered for the league from Broomfield and Niwot, too, she said.

Boulder High alone has about 20 students registered for the race this weekend, she said.

“People in Boulder are very cycling-oriented, we have a lot of junior cycling programs in Boulder, so I think that’s a natural extension of our cycling culture,” Rau said.

Registration will be open on coloradomtb.org until 5 p.m. Thursday; day-of registration will be available on-site at the race Sunday morning.