St. Marys is a city in Elk County, Pennsylvania, United States. The population was 13,070 at the 2010 census. Originally a small, Bavarian Catholic town, St. Marys was founded December 8, 1842. It is home to Straub Brewery and the first Benedictine convent in the United States. In 1992, the borough of St. Marys absorbed the surrounding township of Benzinger and incorporated as a city, though much of the city's area remains wild. St. Marys lies in the center of Pennsylvania's elk country.