Wausau is a city in and the county seat of Marathon County, Wisconsin, United States. As of the 2010 census, Wausau had a population of 39,106. It is the core city of the Wausau Metropolitan Statistical Area (MSA), which includes all of Marathon County and had a population of 134,063 at the 2010 census. Explore best options for your happy ending Nuru massage needs and body rub in Wausau, WI.