is a city in Pleasants County, West Virginia, in the United States. The population was 2,017 at the 2000 census. It is the county seat of Pleasants County. St. Marys was established in 1849 by Alexander Creel, who is said to have had a vision of Mary while passing the townsite by boat on the Ohio River.
St. Marys is part of the Parkersburg-Marietta-Vienna, WV-OH Metropolitan Statistical Area.
St. Marys is located at (39.396393, -81.199701), along the Ohio River at the mouth of Middle Island Creek. Middle Island, which is part of the Ohio River Islands National Wildlife Refuge, is located in the Ohio opposite St. Marys; a bridge connects the city to the island.
According to the United States Census Bureau, the city has a total area of 1.0 square miles (2.5 km²), all of it land.