Located in the Amador Valley, the population was 79,871 at the 2020 census. In 2005 and 2007, Pleasanton was ranked the wealthiest middle-sized city in the United States by the Census Bureau. Pleasanton is home to many large companies yet still maintains its small town charm. Pleasanton is also the home of The Alameda County Fairgrounds, where the county fair is held during the last week of June and the first week of July every year.