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.
AdPlan your weekend with must-see destinations and events in Boulder, Colorado. Find the top-rated and best-reviewed tours and activities in Boulder, Colorado for 2025.
24/7 customer service · Easy price comparison · Contactless experiences
AdFind discounts on the best BoulderColorado Vacation. Tripadvisor helps you spend less. Save money & book with Tripadvisor, the world's largest travel website.