Horner Cycling Foundation’s Thrilla Cyclocross Series is set for the Athletic Club of Bend on four Thursdays (Sept. 12 through Oct. 3).

Registration is now open for the Horner Cycling Foundation’s Thrilla Cyclocross Series, according to a news release. There are no entry fees, as it is a donation-based event.

The series will be held every Thursday in September — Sept. 7, 14, 21, 28 — at the Athletic Club of Bend. Registration is available at www.obra.org.

Cyclocross is the sport of racing bicycles over rough terrain that usually requires carrying the bike over obstacles. Cyclocross bikes are not required but encouraged.

The course is a lap around the Athletic Club, clockwise. Each lap is close to 2 miles. Racers complete as many laps as they can in 30 or 45 minutes, depending on which race they sign up for.

The course is mostly singletrack, loose dirt, two barriers, sand pit (sometimes mud pit), a little pavement and a few steep climbs.

Participants and spectators are encouraged to donate to assist with covering the cost of the event, in lieu of race entry fees.

The Horner Cycling Foundation’s mission is to “make their cycling program and events accessible to all households and participants, regardless of a participant’s ability to pay,” according to the release. All donations will be used to cover expenses related to the event, with any additional funds used for on-going programs and events with the foundation.

For more information, visit www.hornercyclingfoundation.org.

— Bulletin staff report