Aspen Center for Environmental Studies packs in tours and community programs

Staff report
Hallam Lake is the site where several ACES programs are scheduled this summer.
Dale Filhaber/Special to The Aspen Times

Since the late 1960s, ACES has offered community programs and events that introduce locals and visitors of all ages to the incredible natural environment surrounding Aspen, Basalt, and the Castle Creek Valley.

ACES welcomes the public to its visitor centers: Hallam Lake, a 25-acre nature preserve in the heart of Aspen and Rock Bottom Ranch, an educational, regenerative ranch between Basalt and Carbondale. The Catto Center at Toklat, a wilderness retreat near the headwaters of the Castle Creek River remains closed for renovations until late fall 2023. Admission is free at all of these sites. Hallam Lake Nature Preserve and Rock Bottom Ranch feature interactive activities for all ages and staff on-site to answer questions.

For more information, see descriptions below or visit


No reservations required. Space limited, first come, first served. June 17-September 4

Aspen Mountain Hike

Daily on the hour, 11 a.m.-3 p.m., Free

Richmond Ridge: Meet at the top of the gondola for a one-mile guided tour with an ACES naturalist. Wildflowers, wildlife, and mining history, forest ecology, and a 360-degree viewpoint.

Snowmass Wildflower Walk

Daily at 10 a.m., Free

Snowmass Mall: Learn about local ecology and wildflowers as this 2.5-mile loop hike winds in and out of lush meadows and aspen forests.

Snowmass Ice Age Discovery Hike

Daily at 1 p.m., Free

Snowmass Mall: Learn about the Ice Age archaeological discovery in Snowmass. Hike is next to the site of the fossil discovery.

Maroon Bells Maroon Lake Walk

Daily at 10:15 a.m. and 1:15 p.m., Free

Maroon Bells Visitor Center: One-mile, one-way guided tour.

Maroon Bells Crater Lake Hike

Daily at 10:15 a.m. and 1:15.p.m., Free

Maroon Bells: Learn about local ecology and natural history on this two-mile, 500-foot elevation gain, one-way hike from Maroon Lake to Crater Lake.


Walk on the Other Side

July 28, Aug. 25, and Sept. 7, 9 a.m.-1 p.m., Free

North Star Nature Preserve: Join ACES Naturalist Program director to learn about life on the far side of the North Star Preserve. In partnership with Pitkin County Open Space & Trails.

Stories Told by Trees: Fire Walk Series*

Various dates June 22- Sept. 28, Free

Various locations: Join ACES forest and climate Director to learn about forest fire burn zones to learn about the regeneration of forest ecosystems.


Green World Day Hike

Available daily from 10:30 a.m.-2:30 p.m., $60 per person, two-person minimum.

Explore the historic silver mining ghost town of Ashcroft and hike along Castle Creek encountering wildflower meadows and mountain vistas. This 3.5-mile round trip hike features lunch at the Pine Creek Cookhouse. (Cost of lunch not included.)

River Run Sunset Hike

Available July-September, $60 per person, two-person minimum.

For this evening version of “Green Day World Hike,” explore the Castle Creek Valley at sunset and hike to the Pine Creek cookhouse for dinner. (Cost of dinner not included.)


You can go with a naturalist guide on your next hike. Guided tours can be customized to your interests, including wildlife, history, ecology, wildflowers, and more. Sites include Linkins Lake, Ashcroft Ghost Town, Aspen Mountain, Hunter Creek, Maroon Lake, North Star Preserve, American Lake, Lost Man Loop, Cathedral Lake, and sections of the Castle Creek Valley.

Reservations required at or call 970.925.5756.


Led by ACES bird guide Rebecca Weiss.

Morning Birding: Tuesday mornings, weekly, start times vary, Hallam Lake or Rock Bottom Ranch, all experience levels welcome.

Birding By Habitat Series


  • June 21, 7 a.m.-12 p.m. – Basalt Mountain
  • July 12, 7 a.m.-11:30 a.m. – Riverdance
  • July 26, 7 a.m.-10:30 a.m. – Woody Creek & Lenado
  • Aug. 2, 7 a.m.-11:30 a.m. – Snowmass

Observe and discover the diverse bird life in various Roaring Fork Valley habitats.

Birding at North Star Nature Preserve

Monday, July 17, 7-11 a.m.

Wednesdays, Aug. 16 and Sept. 6, 7:30-10:30 a.m.

North Star Nature Preserve

In partnership with Pitkin County Open Space & Trails.

Hummingbird Study

Tuesday, July 11, 7:45-9 p.m.

Thursday, July 13, 7:30-9:30 a.m.

Aspen Area, West Buttermilk Road.


Bird of Prey Demonstrations

Monday-Saturday, June 17-Sept. 4, 5 p.m. at Hallam Lake Nature Preserve

Advanced registration required, free for members, suggested $10 donation for non-members.

Join ACES naturalists and learn about the keystone predators that help keep ecosystems healthy. This program will focus on educating around ACES’ resident birds of prey and new training protocols. Flight demonstrations and/or feedings will be included in this program. Learn more at

Sunset Beaver Walks

June 20-Aug. 30, Tuesdays and Wednesdays, 7:30 p.m. at Hallam Lake Nature Preserve.

Advanced registration required, free for members, $10 per family for non-members.

Join ACES naturalists for sunset beaver walks, a special evening program at Hallam Lake. Learn all about this species and the role beavers play in wetland ecosystems. Guided walk around the Hallam Lake nature preserve at dusk. There will be no Beaver Walk Tuesday, July 4 or August 15. Learn more:

Know Your Trees

Mondays, June 19-Aug. 28, 4 p.m. at Hallam Lake Nature Preserve.

Advanced registration required, free for members, suggested $10 donation for non-members.

Explore ACES’ backyard and discover up to a dozen species of conifers and deciduous trees. Join the ACES Naturalist Program Director Jim Kravitz or the ACES Forest Program Director Adam McCurdy on this hour-long walk around the Hallam Lake neighborhood to identify local trees. Participants will walk away with The Rocky Mountain Tree Finder booklet and basic knowledge about the native trees that grow in our neighborhood. There will be no class on Monday, July 4Learn more at

Wild Yoga

June 20, June 27, July 11, July 18, July 25, 5:15 p.m. at Hallam Lake Nature Preserve.

Advanced registration required, free, suggested $10 donation.

Lead With Love instructors in this outdoor yoga class along the edge of Hallam Lake. Drawing on the roots of yoga, this all-levels class blends philosophy, asana (posture) practice, and contemplative exploration of ACES’ nature preserve. Classes are donation-based and support environmental education programs. In partnership with Lead With Love, 100% of the proceeds support ACES environmental education programs. Learn more at

Sound Bath & Forest Bathing

June 21, July 12, July 26, Aug. 23, 5:15 p.m. at Hallam Lake.

Join Aspen local Megan DiSabatino for a restorative sound journey and forest bathing in nature at Hallam Lake. Will happen rain or shine. More at


Painting & Birding

Wednesday, June 14, 5:30-8 p.m., $75 at Rock Bottom Ranch in collaboration with The Art Base.

High in the Alpine: Flowers, Birds, & Small Mammals of the Tundra

Friday, July 14, 8:30 a.m.-1 p.m., free for members, $10 nonmembers, Independence Pass in partnership with the Forest Conservancy.

Nature Journaling

Saturday, Aug. 5, 9 a.m.-3 p.m., $85

Thursday, Aug. 17, 9 a.m.-1 p.m., $65



Hayride Farm Tours

Saturdays, June 4-Aug. 27, 10:30-11:30 a.m.

Advanced registration required, $10 for adults; children 12 and under free.

See how livestock, hoop houses, and gardens produce through the summer while learning the science behind our vegetable production and livestock rotational grazing system. Tours are appropriate for all ages and provide opportunities to interact with our farmers and learn where food comes from.

More info at

Self-guided Tours

During hours of operation, June-September, 10:30 a.m.

Advanced registration required, suggested $5 donation, $10 for families, free for members.

Explore Rock Bottom Ranch at your own pace. Pick up a copy of self-guided tour and walk around the property, learning about hoop houses, livestock, and more.

More info at

Egg Collection

Fridays, June-September, 10:30 a.m.

Advanced registration required, $10 per family, includes a dozen eggs.

Colorful flock of laying hens, learn their breeds and roles at Rock Bottom Ranch, and help collect multi-colored eggs rain or shine. Egg collection will start promptly at 10:30 a.m.

More info at


WineInk: Aspen and Snowmass

As if we needed any more validation that Aspen and Snowmass are great wine destinations, a couple of recent events, one in Snowmass and one in London, provided added proof.

See more