Help keep our trails and parks open during COVID-19 by committing to social distancing. Some trails or park services may be closed this weekend so check with local authorities before heading out.
Learn more

Best trails in Boulder

44,477 Reviews
Looking for a great trail near Boulder, Colorado? AllTrails has 178 great hiking trails, trail running trails, mountain biking trails and more, with hand-curated trail maps and driving directions as well as detailed reviews and photos from hikers, campers, and nature lovers like you. If you're looking for the best trails in Rocky Mountain National Park, we've got you covered. You'll also find some great local park options, like Genesee Park or Boulder Open Space. Just looking to take a quick stroll? We've got 75 easy trails in Boulder ranging from 0.6 to 20.1 miles and from 5,114 to 9,183 feet above sea level. Start checking them out and you'll be out on the trail in no time!
Show more
Map of trails in Boulder
Top trails (178)
#1 - Royal Arch Trail
Boulder Open Space
hardYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarGray Star(4712)
Length: 4 mi • Est. 2 h 37 m
Start on Chautauqua Trail by the ranger station. After crossing a grassy meadow, you enter a pine forest. Start paying attention to signs for Royal Arch as a number of other trails branch off. You knoShow more
#2 - Mount Sanitas and Sanitas Valley Loop Trail
Boulder Open Space
hardYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarGray Star(2203)
Length: 3.2 mi • Est. 2 h 8 m
While parts of this hike are dog friendly, dogs are not allowed on the Lions Lair section of the trail. A wonderful "desert like" hike with great rock formations, vistas of Boulder CO, and rock scrambShow more
#3 - First and Second Flatirons Loop
Boulder Open Space
hardYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarGray Star(1407)
Length: 2.5 mi • Est. 1 h 59 m
The flatirons are striking, tilted, sandstone rock slabs that form Boulder's beautiful backdrop. There are five distinct flatirons on the western side of Boulder. The route on this page takes you to tShow more
#4 - Chautauqua Trail
Boulder Open Space
moderateYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarGray Star(1630)
Length: 1.2 mi • Est. 46 m
This trail basically serves as the first "in-trail" that leads to many other popular hikes in the park such as the Flat Irons and Royal Arch. It is wide, well traveled, and slightly inclined, with vaShow more
#5 - Green Mountain West Trail
Boulder Open Space
moderateYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarGray Star(1418)
Length: 4 mi • Est. 1 h 38 m
Please note: The Sacred Cliffs at 7,978 feet are closed until August 1st due to nesting raptors.Show more
#6 - Bear Peak via the Shadow Canyon Trail
Boulder Open Space
hardYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarGray Star(864)
Length: 8.1 mi • Est. 4 h 17 m
The trail starts out very easy with well maintained walking trails. As you progress deeper and higher the terrain increases in difficulty; to the point of being slightly technical. The trail gets fairShow more
#7 - Walker Ranch Loop Trail
Walker Ranch Park
hardYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarGray Star(1036)
Length: 8.3 mi • Est. 4 h 27 m
Walker Ranch is a fantastic loop that can be taken both clockwise and counter. Going counter clockwise starts you off on a fantastic downhill, just be careful for hikers and dogs. Once at the bottom, Show more
#8 - Mallory Cave
Boulder Open Space
moderateYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarGray Star(1035)
Length: 2.4 mi • Est. 1 h 31 m
NOTE: The cave itself is permanently closed to reduce human contamination that can cause white-nose syndrome in bats. This hike starts at the NCAR parking lot. Head west to the Mesa trail and cross iShow more
#9 - Green Mountain Loop
Chautauqua Park
hardYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarGray Star(767)
Length: 7.2 mi • Est. 4 h 11 m
Note: There are no dogs allowed on the last mile **of the clockwise route**. If you want to take your dog to the summit ascend via the counterclockwise route or go clockwise and then use the E.M. GreShow more
#10 - Gregory Canyon, Range View and Flagstaff Trail Loop
Boulder Open Space
moderateYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarYellow StarGray Star(1003)
Length: 3.6 mi • Est. 2 h 16 m
This is a great moderately challenging loop with excellent views throughout. The trail is steep but generally well-shaded through the Flatirons. Most of it consists of single-track trail, except for aShow more
Showing results 1 - 10 of 178