When Is Peak Aspen Season in Colorado?

Colorado's aspen season peaks between mid-September and mid-October, depending on elevation. High-country groves above 10,000 feet — Kebler Pass and Boreas Pass Road — typically peak in the last week of September; mountain valleys and mid-elevation spots like Bear Lake, Twin Lakes, and the Vail Valley follow close behind, into the first week of October; and the true Front Range foothills near Denver and Boulder peak latest, in the first two weeks of October. There's no single statewide date — color moves downhill as a rolling wave over roughly a month.

Why There's No Single "Peak" Date

Aspens change color in response to cooling temperatures and shortening days, and both of those hit high elevations first. A grove at 11,500 feet can be past peak while a grove at 8,000 feet, twenty miles away, hasn't started. That's why "Colorado aspen season" isn't one weekend — it's a rolling window that starts in the high country in mid-September and finishes in the foothills in mid-October.

A Realistic Timeline, By Elevation

• High country (10,000'–11,500'+) — places like Kebler Pass (10,007') near Crested Butte and Boreas Pass Road above Breckenridge (11,481' at the summit). This is where it starts, typically peaking in the last week of September.
• Mountain valleys and mid elevation (8,000'–10,000') — places like Bear Lake in Rocky Mountain National Park (9,450'), Twin Lakes (9,600'), and the Vail Valley (around 8,150'). Peak color usually lands from the last few days of September into the first week of October, close behind the high country rather than far behind it.
• Front Range foothills (under 8,000', Denver/Boulder area) — the last wave, typically peaking in early-to-mid October, though the exact window shifts more year to year here than at higher elevations.

Those windows shift year to year with weather — an early hard frost speeds things up, a warm, dry September can stretch peak color out or delay it slightly — but the order rarely changes. High country goes first, foothills go last.

Where to See It

Kebler Pass is one of the best-known aspen drives in the state, and at just over 10,000 feet it's one of the first places to turn. Autumn Aspen Grove and Autumn Reflections on Kebler Pass were both shot there, alongside Fall Sunrise Vista from Boreas Pass Road above Breckenridge, higher still at over 11,000 feet.

Close behind the high country, Bear Lake in Rocky Mountain National Park (9,450'), Twin Lakes (9,600'), and the Vail Valley (around 8,150') all hold color from late September into the first week of October — Autumn Shoreline, Mt Hope and Rinker Peak, Forest of Green and Gold, and Colors of Fall were all shot in this window. The true last wave is lower still — the Front Range foothills near Denver and Boulder, which typically hold color into mid-October. Autumn at Sawhill Ponds was shot at Sawhill Ponds, on the plains just east of Boulder.

The full range of aspen and fall foliage images — including locations not mentioned here — is in the Aspen Trees collection.

How to Time a Trip

If you can only make one trip, pick your elevation first and work backward from there. Heading to Kebler Pass, Boreas Pass Road, or another high-country grove above 10,000 feet, aim for the last week of September. Heading to Bear Lake, Twin Lakes, or the Vail Valley, give it a few days to a week later. Heading to the Front Range foothills near Denver or Boulder, plan for early-to-mid October. Local ranger districts, OpenSnow, and Colorado tourism sites publish real-time fall color reports in September, which is the most reliable way to fine-tune the exact week once you're within a month of going — timing shifts noticeably from year to year with drought and frost conditions.

For a first-hand account of how one season actually played out, including weather and timing notes, see Autumn in Colorado 2024. For tips on photographing the season yourself, see Fall's Golden Palette.

Frequently Asked Questions

When exactly does Colorado's aspen season start?

High-elevation groves like Kebler Pass typically begin changing in early-to-mid September, with peak color arriving in the last week of September. Lower elevations start later and peak into early-to-mid October.

Is Kebler Pass or Rocky Mountain National Park better for peak color?

Kebler Pass sits higher and tends to peak first, in the last week of September. Rocky Mountain National Park spans a wider elevation range, so its color moves from high peaks in late September down to Bear Lake's elevation by early October — a good option if you missed Kebler Pass's window.

How long does peak color actually last?

At any single elevation, peak color usually holds for about a week to ten days before a hard frost or wind brings the leaves down. Because Colorado's elevations span thousands of feet, the overall season across the state runs three to four weeks even though any one spot's peak is much shorter.

Does a dry or wet summer change the timing?

It can shift things by several days in either direction and affect how vivid the color is, but it doesn't change the basic order — high elevation still goes first, foothills still go last.

Can I get a print of a specific location shown here?

Yes — every image links to its product page, and the full Aspen Trees collection has more from these same locations. Get in touch if you're looking for a specific place that isn't in the collection yet.

Ready to see the full collection? Browse the Aspen Trees collection or see the full gallery.

Sources: elevation figures for Kebler Pass, Boreas Pass, Bear Lake, Twin Lakes, and Vail via Wikipedia; fall color timing via the National Park Service, Estes Park, Vail.com, and OpenSnow via Vail Daily.