UpaDowna Climb Nights - 6-8 p.m., second Tuesday, CityRock, 21 N. Nevada Ave., free. Registration: upadowna.org/programs.
Pizzeria Rustica Cycling Club - 2 p.m. second Sundays, Pizzeria Rustica, 2527 W. Colorado Ave.; pizzeriarustica.com.
Garden of the Gods Visitor and Nature Center sponsored hikes - 1805 N. 30th St., free; 219-0104. - Get Fit in the Garden Wellness Walk, 9 a.m. Wednesdays. Register in person.
Bear Creek Nature Center hikes - 245 Bear Creek Road. Reservations: 520-6387. - Winter Woodland Wonders Walk at Fox Run, 10 a.m. Saturday, $4. - Active Adult Series: Full Moon Hike, 6 p.m. Jan. 31, $4.
Mueller State Park hikes - 21045 Colorado 67, Divide. Day pass $7 per vehicle; 687-2366. - Elk Meadow to Murphy's Cut, 9:15 a.m. Friday, Elk Meadow Trailhead. - Elk Meadow, 1:30 p.m. Sunday, Elk Meadow Trailhead. - Rock Pond, 9:15 a.m. Jan. 19, Visitor Center. - Elk Meadow, 9:15 a.m. Jan. 27, Elk Meadow Trailhead.
Nature programs at Fountain Creek Nature Center - 320 Peppergrass Lane, Fountain. Reservations: 520-6745. - 2's & 3's Outdoors - Silly Squirrels, for ages 2 and 3, 10-11:15 a.m. Thursday, $3. - Fountain Creek Winter Bird Count, 8:30-11 a.m. Saturday, $5.
Nature programs at Bear Creek Nature Center - 245 Bear Creek Road. Registration: 520-6387. - Kids' Winter-iffic Night Out, for children in grades 1-5, 5:30-9 p.m. Friday, $15. - Nature Explorers: Birding for Tots, for ages 4-5 with an adult, 10-11:30 a.m. Jan. 17 and 18, $3. - Aiken Audubon Monthly Program: Twenty-five Years of Christmas Bird Counts, 7 p.m. Jan. 17, free. - Little Wonders: Hibernation Station, for ages 2 and 3, 10-11:15 a.m. Jan. 24 and 25, $3.
Nature programs at Starsmore Discovery Center - 2120 Cheyenne Canyon Road; 385-6086. - Winter Festival: Birds of Winter, 10 a.m.-2 p.m. Jan. 27, $5 per family.
Better Bird Watching - With wildlife biologist Joe LaFleur, 2 p.m., Woodland Park Public Library, 218 E. Midland Ave., Woodland Park, for ages 10 and older; 687-9281, rampartlibrarydistrict.org.
International Sportsmen's Expo - Noon-8 p.m. Thursday and Friday, 10 a.m.-7 p.m. Saturday, 10 a.m.-5 p.m. Sunday, Colorado Convention Center, 700 14th St., Denver, $16, free for children 15 and younger; sportsexpos.com/attend/denver.
Pikes Peak Road Runners - Go online for information, cost and registration: pprrun.org. - Winter Series I, 10 a.m. Saturday, Cheyenne Mountain State Park.
Thursday Night Run Club - 6 p.m. Thursdays, Old Chicago's, 7115 Commerce Center Drive; 232-4656, facebook.com/TNRCCOSprings.
Catamount Institute - 2740 E. Caramillo St.; 471-0910, catamountinstitute.org. - Volunteer Training, 5:30-7 p.m. Jan. 18.
Fountain Creek Nature Center - 320 Peppergrass Lane, Fountain. Registration: 520-6745. - MLK Service Day, 10 a.m.-noon Jan. 20.
Mueller State Park - 21045 Colorado 67, Divide, needs volunteers for naturalist programs, backcountry-trail maintenance, newsletter editing or work in the visitor center. Training is provided; 687-2366.
Bear Creek and Fountain Creek nature centers - Needs volunteers for assisting with environmental education programs and visitor information services; Paula Megorden, 520-6387, email@example.com.
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