Welcome to Arapahoe County, Colorado - the state s first county and the third largest with a population of more than 572,000. Arapahoe County was named for the Arapaho Indians, who along with the Cheyenne Indians, occupied most of Colorado when it was only a territory.
Back then, Arapahoe County was much larger - stretching east to western Kansas. Denver was the original County seat until 1902 when the city split off and became a separate county. The City of Littleton became the new county seat and remains the county seat today. The County Administration Building is located at 5334 S. Prince Street in Littleton, Colorado.
Arapahoe County has 1,900 employees and a $324.4 million budget. Arapahoe County has one of the lowest mill levies in the Front Range.