Things to do outside in Boulder
The best outdoor things to do in Boulder, Colorado are hiking the Flatirons trails, rock climbing in Eldorado Canyon, swimming and paddling at Boulder Reservoir, camping up the canyons, and biking everything from the Boulder Creek Path to Betasso singletrack. Here's how it all fits together, with a full guide behind each one.
Outdoor Boulder › Things to do outside
Boulder is built for the outdoors
Few cities put this much wild land at the edge of downtown. The City of Boulder's Open Space and Mountain Parks system alone protects roughly 45,000 acres and more than 155 miles of trails, and that's before you count the county parks, the state park in Eldorado Canyon, and the national forest peaks up the canyons. You can be on a real trail, on the water, or on a bike within minutes of the city center.
This is the outdoor guide, so that's all we cover here: the things to do outside, organized by what you feel like doing and where you feel like going. For the sit-down-and-eat side of a Boulder trip you'll want a full city guide; for everything that gets you outside, start below and follow the link into the full guide for whatever catches your eye.
Outdoor things to do in Boulder, by activity
Five ways to get outside here. Each links to its own hub with the specific trails, put-ins, and spots, plus parking and rules.
Hiking
The main event: flat creekside paths, steep foothill climbs, and the classic Flatirons trails, all sorted by difficulty.
Rock climbing
One of the sport's home bases, from the sandstone Flatirons to the walls of Eldorado Canyon, plus where a beginner should start.
Swimming & paddling
Summer swim beaches, flatwater paddling, and tubing the creek, at Boulder Reservoir, Gross Reservoir, and the Boulder Creek Path.
Camping
Campgrounds in the foothills and up the canyons, from drive-up sites to quieter mountain spots near Nederland and the Peak to Peak.
Biking
The paved Boulder Creek Path through town, flowy singletrack at Betasso Preserve, and the long road climbs the pros train on.
Outdoor things to do in Boulder, by destination
Rather pick a place than an activity? These are the destinations worth building a day around. Each guide has the verified facts, parking, and dog rules for that spot.
Chautauqua Park
Boulder's front porch to the Flatirons: a meadow, a historic dining hall, and the trailhead for most of the famous hikes.
Eldorado Canyon
A state park canyon with world-class climbing, a wild creek, and hiking, just south of town.
Mount Sanitas
A steep, quick, stair-stepped loop to an open summit right above west Boulder.
Boulder Reservoir
The go-to spot to swim, paddle, and walk the shoreline, with a staffed summer swim beach.
Royal Arch Trail
A rocky climb from Chautauqua to a natural sandstone arch framing the city.
Brainard Lake
Alpine lakes beneath the Indian Peaks, about an hour up the canyon, for high-country hiking and paddling.
Nederland
The mountain-town gateway to Indian Peaks, alpine lakes, and the Peak to Peak Scenic Byway.
More Boulder destinations, including NCAR and the Mesa Trail, Betasso Preserve, the Boulder Creek Path, Gross Reservoir, and Walker Ranch, each have their own guide too. See all destinations.
Planning your Boulder outdoor visit
Three things trip up first-time visitors here, and all three are easy to plan around.
Altitude. Boulder sits at about 5,430 feet, and the trails climb from there, so the air is thin and the sun is strong. Drink more water than feels necessary, take it easy your first day, and wear sunscreen even when it's cool.
Weather. The front range gets a lot of sun, but summer afternoons build fast thunderstorms. Start early and be off exposed ridges and summits by early afternoon. Mountain weather up the canyons runs colder and can hold snow into early summer.
Parking. This is the real hurdle at Boulder's popular trailheads. Chautauqua and other OSMP lots fill early on summer weekends and charge for parking then, and a free seasonal Park-to-Park shuttle runs from downtown on those busy days. Boulder Reservoir charges a day-use entry fee in the warm months. Come early or come on a weekday. For a fuller pre-trip rundown, see plan your visit on the home page.
When to go: Boulder's outdoor seasons
There isn't a bad season to get outside in Boulder, just different ones.
- Summer (June to August): peak water season. Swim and paddle at Boulder Reservoir, tube the creek, and drive up to Brainard Lake once the high country melts out. Plan around afternoon storms.
- Fall (September to October): arguably the best hiking, with cool air, gold aspens up the canyons, and thinner trailhead crowds.
- Winter (November to March): sunny, lower foothill hikes like Mount Sanitas often stay snow-free on south-facing slopes, while Nederland and the high country open up for snowshoeing and cross-country skiing.
- Spring (April to May): the front-range trails dry out first while the peaks are still white. Expect mud after storms and stick to lower, well-drained routes.
Outdoor Boulder: frequently asked questions
What are the best free outdoor things to do in Boulder?
Most of Boulder's best outdoor activities are free. Hiking the Open Space and Mountain Parks trails, like Mount Sanitas, Royal Arch, and the Chautauqua meadow, costs nothing, and walking or biking the Boulder Creek Path through town is free too. The main costs are parking at popular trailheads and the day-use entry fee at Boulder Reservoir. Bring your own water and layers and you can fill a whole day for free.
What can you do outside in Boulder with kids or a dog?
For kids, the flat Boulder Creek Path, the Chautauqua meadow, and the Boulder Reservoir swim beach are easy wins. For dogs, Boulder's OSMP trails are unusually dog-friendly: with a City of Boulder Voice and Sight tag, dogs can hike off-leash on many trails as long as they are truly under control and leashed at the trailhead. Boulder Reservoir restricts dogs along the swim area in summer, so check each guide before you go.
What is there to do outdoors in Boulder on a rainy day or in the off-season?
Boulder gets a lot of sun, so wet days are usually short. When the high trails are muddy or snowy, the paved Boulder Creek Path drains and clears fast, and lower foothill trails like the Sanitas Valley Trail stay walkable. In the off-season, an indoor climbing gym is a solid backup, and the front-range trails often melt out days before the high country does.
What are the best outdoor things to do in Boulder in summer versus winter?
In summer, swim and paddle at Boulder Reservoir, tube Boulder Creek, and drive up to the alpine lakes at Brainard Lake once the snow clears (usually by July). In winter, stick to the sunny, lower foothill hikes, which often stay snow-free on south-facing slopes, and head up toward Nederland for snowshoeing and cross-country skiing. Summer afternoons bring fast thunderstorms, so start early either way.
Do you need a car to enjoy the outdoors in Boulder?
Not for everything. From downtown you can walk or bike straight onto the Boulder Creek Path, and a free seasonal Park-to-Park shuttle runs to Chautauqua on busy summer weekends and holidays. But the higher destinations, like Brainard Lake, Nederland, and Eldorado Canyon, are up the canyons and effectively need a car. In town, a bike gets you almost anywhere you'd want to go outside.
Recommended locally
[CLIENT SLOT: featured Boulder gear shop]
[One honest line: where to grab shoes, water, layers, or a daypack before you head out.]
[CLIENT SLOT: featured guide service or rental]
[One honest line: a local outfitter for climbing lessons, bike rentals, or paddle craft.]
[CLIENT SLOT: featured place to stay]
[One honest line: a well-placed base for a Boulder outdoor weekend.]
Sources
The open-space acreage and trail-mileage figures on this page come from the City of Boulder. Per-destination facts, parking prices, and dog rules live on each linked guide, with their own sources.