Colorado Springs Cycling Club — For all ages and abilities; bikesprings.org.
Rocky Mountain Conservancy Field Institute — Hike with a naturalist, 1895 Fall River Road, Estes Park. Register: rmconservancy.org.
• Estes Cone, Saturday.
Garden of the Gods Visitor and Nature Center — 1805 N. 30th St., free; 219-0104.
• Get Fit in the Garden Wellness Walk, 9 a.m. Wednesdays. Registration required.
Mueller State Park — 21045 Colorado 67, Divide. Day pass $8 per vehicle; 687-2366.
• Homestead Trail, 9 a.m. Tuesday, Homestead Trailhead.
• Preacher’s Hollow, 9 a.m. Thursday, Preacher’s Hollow Trailhead.
• Cheesman Trail, 8 a.m. Friday, Grouse Mountain Trailhead.
• Cahill Loop, 10 a.m. Friday, Grouse Mountain Trailhead.
• School Pond and Stoner Hill, 8 a.m. Saturday, School Pond Trailhead.
• Lost Still, 3 p.m. Sunday, Ground Mountain Trailhead.
COTREX — Colorado’s official trails App; trails.colorado.gov.
Rocky Mountain Raptor Program — 720 East Vine Drive, Fort Collins; 970-484-7756, rmrp.org.
• 11 a.m.-3 p.m. Saturday.
Mueller State Park — 21045 Colorado 67, Divide. Day pass $8/vehicle; 687-2366.
• History of Early Explorers and Military in Pikes Peak Region, 8 a.m. Thursday, Amphitheater.
• Western Heritage Day, 10 a.m.-2 p.m. Saturday, Visitor Center and Library.
Fountain Creek Nature Center — 320 Peppergrass Lane, Fountain. Register: 520-6745; tinyurl.com/yarxcazm.
• Monarch Magic, 10-11:30 a.m. Saturday, $5.
Bear Creek Nature Center — 245 Bear Creek Road. Register: 520-6387; tinyurl.com/yarxcazm.
• Children’s Nature Explorers, 9-10:30 a.m. Wednesday-Thursday, 1-2:30 p.m. Wednesday, $3.
• Pikes Peak Mycological Society Program, 6-8 p.m. Wednesday, free.
Florissant Fossil Beds National Monument — Florissant, entrance fee, $10 for 16 and older; 748-3253.
• Coffee and Cake with a Park Ranger, 10 a.m.-3 p.m. Tuesday, free.
• Night Sky Program, 8-10 p.m. Friday.
Hutchinson Homestead Ranch and Learning Center Tours — Salida, $5, $3 for ages 8-16; 239-0955, hutchinsonhomestead.org.
Colorado Running Co. — For a list of runs and events: corunco.com.
Mountain Post Running Club — 5K or 10K, 4-6 p.m. Wednesdays, Main PX, 6220 Martinez St., Fort Carson, free. Children, strollers and pets welcome; Kris Spiller, firstname.lastname@example.org.
Two Elks Runners Club — 5:30-7 p.m. Thursdays, Thunder and Buttons, upstairs, 2415 W. Colorado Ave. Run along Midland Trail; 447-9888, email@example.com or on Facebook.
Pikes Peak Run Fest — 5-8 p.m., Memorial Park, 502 Manitou Ave., Manitou Springs, free; pikespeak marathon.org.
Mueller State Park — 21045 Colorado 67, Divide, needs volunteers for naturalist programs, trail maintenance, newsletter editing or work in visitor center. Training provided; 687-2366.
Bear Creek and Fountain Creek nature centers — Help with environmental education and visitor information; Paula Megorden, 520-6387, firstname.lastname@example.org.
Garden of the Gods Visitor and Nature Center — Volunteer for the information desk; Bret Tennis, 219-0108.
Listings are published on a space-available basis. Email information at least two weeks in advance: email@example.com.