UpaDowna Climb Nights — 6-8 p.m., second Tuesday, CityRock, 21 N. Nevada Ave., free. Register: upadowna.org/programs.
Bike Festival — Group rides, bike films, chainless race, bike parade, Salida; salidachamber.org.
CannaVenture Hikes — Free. Register: cannaventure.org.
• Elk Falls Overlook, 10 a.m.-5 p.m. Sunday, Staunton State Park, Pine.
Garden of the Gods Visitor and Nature Center — 1805 N. 30th St., free; 219-0104.
• Daily Guided Nature Walks, 10 a.m. and 2 p.m., meet north main parking lot.
Mueller State Park — 21045 Colorado 67, Divide. Day pass $8 per vehicle; 687-2366.
• Rock Pond and Canyon, 8 a.m. Tuesday, Rock Pond Trailhead.
• Buffalo Rock, 9 a.m. Wednesday, Grouse Mountain Trailhead.
• Preacher’s Hollow, 8 a.m. Thursday, Visitor Center.
• Ranger Ridge and Stoner Mill, 8 a.m. Saturday, School Pond Trailhead.
• Cahill, 10 a.m. Saturday, Grouse Mountain Trailhead.
• Dynamite Cabin, 3 p.m. Sunday, Grouse Mountain.
Florissant Fossil Beds National Monument — Florissant, entrance fee, $10 for 16 or older; 748-3253.
• Geology Hike, 9 a.m. Saturday, Visitor Center.
Rocky Mountain Trails — Information on more than 70 hikes; rockymountainhikingtrails.com.
Florissant Fossil Beds Walk — Hosted by the Falcon Wanderers Walking Club, start between 9:30 a.m.-noon and finish by 3 p.m., Visitor Center, 15807 Teller County Road, Florissant. Walking sticks advised, large-wheeled strollers can complete, wheelchairs can not complete, no pets allowed, free; Curt Converse, 591-8193.
Rocky Mountain Raptor Program Classes — 720 East Vine Drive, Fort Collins, $60. Registration: 1-970-484-7756, rmrp.org.
• Construction of a Predator — Anatomy and Physiology, Saturday.
Mueller State Park — 21045 Colorado 67, Divide. Day pass $8/vehicle; 687-2366.
• Wolves, 7 a.m. Sept. 16, Amphitheater.
Fountain Creek Nature Center — 320 Peppergrass Lane, Fountain. Register: 520-6745; tinyurl.com/yarxcazm.
• 2s & 3s Outdoors: Things that Smell, for ages 2-3, 9-10:15 a.m. Thursday, $3.
• Homeschool Fridays: Awesome Arthropods, for children in grades K-2, 2-4 p.m. Friday, $4.
• Fall Bird County, 7:30-10:30 a.m. Saturday, $5.
Bear Creek Nature Center — 245 Bear Creek Road. Register: 520-6387; tinyurl.com/yarxcazm.
• Webelos Scout Day, 9 a.m.-3 p.m. Saturday, $4 per badge.
Sunrise Nature/Wildlife Photo Shoot — Saturday mornings, Westcliffe, $55. Register: 1-303-823-6399, kennethwajda.com/naturewildlife/.
Colorado Birding Trail — Coloradobirdingtrail.com lists places to see birds and wildlife.
Pikes Peak Road Runners — Cost and registration: pprrun.org.
• Brewers’ Cup Full Moon Run, 6 p.m. Friday, Red Leg Brewing.
• Full Moon Run, 7 p.m. Friday, Red Rock Canyon Open Space.
• 4.9K Walk/Run, 9 a.m. Saturday, Falcon High School.
• PawtoberFest 5K Run/Walk 2M, 10 a.m. Saturday, Bear Creek Park.
• Pony Express 15M, 8 a.m. Sunday, Rampart Range Road, Woodland Park.
• Strides for Epilepsy 5K, 10 a.m. Sunday, 5KMemorial Park.
Bear Creek Nature Center — 245 Bear Creek Road. Register: Paula, 520-6387, email@example.com.
• Volunteer Environmental Education Leader Training, noon-4 p.m. Thursday-Friday.
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