Don’t just rely on our write-ups. Pick up a trail map at an outdoors store like the Ute Mountaineer (210 S Galena St) or visit the Forest Service’s Aspen Ranger Station (806 W Hallam St, by the S-curves) for more detailed information (Note: this summer the station is not open to visitors; for information, call 970-925-3445) . The website pitkinoutside.org has an interactive map of area trails. Also check out aspenrecreation.com and hike.gosnowmass.com for descriptions of trails in Aspen and Snowmass Village, respectively.
Get an early start. Brief afternoon thunderstorms commonly occur in the summer. Leave yourself plenty of time to get down from peaks or high, exposed ridges before a storm hits. And stow a rainshell in your pack.
Acclimate to the altitude. The air is thin up here, and you may find it harder to breathe. Take a couple of shorter hikes closer to town before setting out on a high-alpine adventure. Also allow adequate time to move at higher elevation.
Prep for cooler temps. For a longer hike, pack a fleece or other lightweight but warm layer. The higher you go, the colder it can get, even in the middle of summer.
Carry water and snacks. Stay hydrated with water that you’ve brought. Lakes and streams carry a risk of giardia, a nasty intestinal parasite. Keep from bonking with energy bars, gels, dried fruit, nuts, or whatever your favorite trail snack is.