Ames () is a city in Story County, Iowa, United States, located approximately 30 miles (48 km) north of Des Moines in central Iowa. It is best known as the home of Iowa State University (ISU), with leading agriculture, design, engineering, and veterinary medicine colleges. A United States Department of Energy national laboratory, Ames Laboratory, is located on the ISU campus. According to the 2020 census, Ames had a population of 66,427, making it the state's ninth most populous city. Iowa State University was home to 30,177 students as of Fall 2023, which make up approximately one half of the city's population. Ames also hosts United States Department of Agriculture (USDA) sites: the largest federal animal disease center in the United States, the USDA Agricultural Research Service's National Animal Disease Center (NADC), as well as one of two national USDA sites for the Animal and Plant Health Inspection Service (APHIS), which comprises the National Veterinary Services Laboratory and the Center for Veterinary Biologics. Ames also hosts the headquarters of the Iowa Department of Transportation.