Boulder is famous for the majestic sandstone flatirons jutting from the mountainside above the town. Most people probably know that you can hike these soaring monoliths. The first and second flatiron trail is one of the most popular in Boulder County, climbing 2.7 miles through rocky debris and pine forests to sit among the boulders for which the city is named.

Credit: Sam Grossberg, AllTrails

Our Ratings:

Crowd: 2/5. This is a very busy trail. On fair days and weekends you’ll be following a steady stream of other hikers up and down the mountain. Even at sunrise and during the winter the trail is well populated. If you’re looking for a little taste of solitude, this is not the trail for you. But if you want a fun climb up the mountain with your friends (two-legged or four—this is a dog-friendly trail!) then we highly recommend this trail.

Credit: Anita Law, AllTrails

Views: 4/5. That being said, this trail is crazy popular for good reason! With the majesty of the flatirons to the north and south, it’s a truly iconic location for a selfie. Or soak in the views sans your smartphone: you can see from horizon to horizon from the summit, and glimpse views of the snow-capped Rockies to the west. Ever considered a sunrise hike? This is one of the best locations to watch the sky change as the sun creeps up over the plains.

Credit: Anita Law, AllTrails

Difficulty 4/5. This is rated moderate to hard, and it’s easy to understand why. While there are very few steep scrambles, there is a steady uphill battle between you and that summit. You’ll gain 1262 feet on this trail, much of it in switchbacks. In the summer you may encounter significant swarms of insect life, and in the winter we highly recommend poles and microspikes as the trail gets very icy!

Credit: Bergen Adair

Overall: 4/5. If you can time it right to avoid the majority of the crowds, this is a beautiful and must-see hike that captures the essence of Boulder. Rock climb at the top, snap a pic for Instagram, greet the sun, or soak in nature—whatever you want, there’s something here for you.