Boulder is a home rule city in Boulder County, Colorado, United States, and its county seat. With a population of 108,250 at the 2020 census, it is the most populous city in the county and the 12th-most populous city in Colorado. It is the principal city of the Boulder metropolitan statistical area, which had 330,758 residents in 2020 and is part of the Front Range Urban Corridor.
AdDiscover the unique Boulder, Coloradoactivities designed to make your time unforgettable. Find the top-rated and best-reviewed tours and activitiesinBoulder, Colorado for 2025.
Site visitors: Over 1M in the past month
Over 60,000 activities · Top attraction tickets · Must-see attractions · Skip-the-line tickets