Wausau is a city in and the county seat of Marathon County, Wisconsin, United States. The Wisconsin River divides the city. The city is adjacent to the town of Wausau. According to the 2000 census, Wausau had a population of 38,426 people. It is the core city of the Wausau Metropolitan Statistical Area (MSA), which includes all of Marathon County and had a population of 125,834 at the 2000 census. It is the 297th largest MSA in the United States. Besides Wausau, other significant communities in the metropolitan area include Schofield, Rothschild, Weston, Kronenwetter, and the town of Rib Mountain.