Cell phone service is pretty good through the Flatirons and Eldo; it's spotty at best in Boulder Canyon. Don't expect bars at crags right off the road in BoCan, but you might catch one or two at higher crags -- for example, Animal World has a pocket of service at the top of the approach trail.
Hopefully you'll never need help from Rocky Mountain Rescue Group . But you should know that you can initiate a rescue by dialing 911 or calling Boulder County sheriff's dispatch, 303-441-4444.
Boulder's vast landscape of rock has inspired intrepid climbers and scramblers for a century.
The result? More routes than you could climb in a lifetime.
With so much rock, so much history, so many guidebooks -- and even a mobile version of Mountain Project at your fingertips at the crag -- it's hard to know where to start climbing in Boulder.
Actually, before you start: Whether you're climbing in Eldo, Boulder Canyon or the Flatirons, always check for crag closures when you're climbing around Boulder. Many areas have seasonal closures to protect raptors and other wildlife.
1 West Ridge
All types of cragging opportunities abound on the West Ridge, a massive ridge of sandstone that extends nearly 2,000 feet uphill from the creek.
With so much good trad climbing -- single- to multi-pitch, cruiser to thin to terrifying -- it's easy to lose track of time here and climb whole days away on one section. Go for mornings in warm weather, afternoons in cool temps.
Critter note: Eldo chipmunks love to eat climber's lunches and aren't afraid to climb into your pack or chew through it for a snack. (Actually, this is true at most crags.)
Approach: Three approaches, depending on the time of the year and which section of the West Ridge you're heading to. For upper reaches, or when the creek is at its highest, approach via the Eldorado Canyon Trail to Rincon. Lower, approach the West Ridge Trail by the creek crossing at Milton Boulder or the Streamside Trail. Don't worry -- Steve Levin's guidebook for Eldo will get you there.
2 The Dome
The Dome and the Elephant Buttresses are the first crags up Boulder Canyon, and they're home to trad classics. Trad newbies can get a taste of the canyon's granite slabbiness on the Dome, and those seeking a test piece will find many.
But perhaps the best part of climbing on the Dome is its proximity to town and campus. You can ride your bike to the crag, or sneak in a few pitches on a break between classes, if you're on the ball.
Approach: Less than a mile up Boulder Canyon, pull out (to the left, where there's more parking) at the first obvious crag...or ride your bike there, it's not far. A bridge crosses the creek to access the crags.
3 Gregory Canyon
The routes in and around the Gregory Amphitheater and the first pinnacles make for a good introduction to Flatirons climbing without committing to multiple pitches or the long walk. Most of the routes here are easy -- nice for first leads or first timers --- but there are a handful of tougher ones in the mix, too.
Some of the walls here close part of the year so wildlife can do its thing. Read the signs on the way in if you forget to look online before leaving the house.
Itch note: Keep an eye out for poison ivy here. Even on routes, watch what kind of vegetation you're dragging your rope through.
Approach: Take Baseline Road west past Chautauqua. Turn left for the trailhead where the road kicks right to head up Flagstaff Mountain. Follow the Amphitheater Trail to approach most of the climbs.
4 Animal World
If clipping bolts is your thing, Animal World will be a blast. This crag has fun trad routes, too, and a few routes protect with a mix of bolts and gear, but the moderate-to-tougher sport routes are the biggest draw.
Animal World is mostly south facing, but the routes wrap around the cliffs in a way that makes it possible to chase the sun or shade throughout the day.
Approach: Animal World is less than a mile above (west of) Boulder Falls. Spot the Boulderado, which sits below Animal World, from the road and hike left of this cliff to reach Animal World.
5 Third Flatiron
The Third is a tad big to dub it a crag, but how can you not climb the Third as a climber attending the University of Colorado?
The Third is the iconic Flatiron that still bears the traces of the biggest university-inspired graffiti in town (look closely and you can still see the painted, blocky "CU"). Climb the Standard East Face route (first ascent in 1906, wow) and you'll cross the covered-up "CU" a few pitches from the top.
Aside from the must-do east face, the Third has tons of tougher routes on the sides and back that were put up by Boulder's climbing hardmen decades before you were born. Don't expect soft grades on these classics, but do check them out.
Approach: The approach depends on which part of the Third you're heading to, but all approaches start from Chautauqua.