Natural Lands Trust is inviting area families to take part in its first trail race, the ChesLen Chase for Open Space, on Oct. 25 at the land conservation organization’s ChesLen Preserve in Unionville.

Participants can walk or run through the 1,263-acre ChesLen Preserve, selecting either a 10K run, a 5K run, or a 1.5-mile run/walk. The challenging 10K course leads runners across open fields, through dense woodlands, and around marshy wetlands, and includes steep hills and a creek crossing.

The post-race party will include live music, craft beers and barbeque from Victory Brewing Company, and an awards ceremony.

Chester County Running Store will provide professional timing services and instant results for runners. Race results will also be posted online. The top overall male and female finishers and the top three male and female finishers in six age groups for both the 5K and 10K events will be awarded prizes.

Runners and walkers of all ages are welcome. Ages 12 and younger are free. All registrants for the races will receive an event T-shirt.

Victory Brewing Company will offer one free barbeque sandwich and one free beer (for ages 21 and older) to all participants. Additional sandwiches and beverages will be for sale from Victory’s “Brew Pub on Wheels.”

Registration is $45 for the 10K race, $35 for the 5K race, and $25 for the 1.5-mile fun run/walk. Runners receive a $5 discount if they register on or before Oct. 11. Members of Natural Lands Trust receive an additional $5 discount. Runners who become a fundraiser for the event can race for free.

For more information, visit www.natlands.org/cheslenchase.

Proceeds from the ChesLen Chase for Open Space will benefit Natural Lands Trust’s ChesLen Preserve, one of the largest private nature preserves in southeastern Pennsylvania. The preserve is open to the public, free of charge, during daylight hours seven days a week. Since its founding in 1953, Natural Lands Trust has preserved more than 100,000 acres, including 42 nature preserves totaling more than 22,000 acres.