Aberdeen is a city and the county seat of Brown County, South Dakota, USA, about 125 mi (200 km) N.E. of Pierre. Settled in 1880, it was incorporated in 1882. The city population was 24,658 at the 2000 census. The American News is the local newspaper.
Aberdeen is the principal city of the Aberdeen Micropolitan Statistical Area, which includes all of Brown and Edmunds counties and has a population of 39,827.
Aberdeen is located in northeastern South Dakota, in the James River valley, approximately 11 miles (18 km) west of the river. The James River enters northeastern South Dakota in Brown County, where it is dammed to form two reservoirs northeast of Aberdeen. The city is bisected by Moccasin Creek, a slow-moving waterway which flows south and then northeast to the James River.