Parker: The city of Parker has been ranked No. 2 by Money.com on its 2020 Best Places to Live in America list. Money describes the Douglas County municipality, the county’s second most populous city behind Castle Rock, as a “gorgeous natural setting” with “breathtaking views and plenty of proximity to wildlife.” Parker is a suburb of Denver with a population of 54,352. Parker is in Douglas County and is one of the best places to live in Colorado. Living in Parker offers residents a dense suburban feel and most residents own their homes.