thumb|Pleasants County Courthouse
St. Marys is a city in and the county seat of Pleasants County, West Virginia, United States. The population was 1,847 at the 2020 census.
Train tracks run down the middle of 2nd Street in St. Marys, and freight trains running through the middle of downtown St. Marys are a common sight. It is one of the few remaining towns in the United States where freight trains actually share city streets with automotive traffic.
Geography
St. Marys is located 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 River beside St. Marys; a bridge connects the city to the island.
According to the United States Census Bureau, the city has a total area of , all land.
Demographics
2020 census
As of the 2020 census, St. Marys had a population of 1,831. The median age was 41.8 years. 21.7% of residents were under the age of 18 and 21.8% of residents were 65 years of age or older. For every 100 females there were 94.8 males, and for every 100 females age 18 and over there were 87.3 males age 18 and over.
0.0% of residents lived in urban areas, while 100.0% lived in rural areas.
There were 799 households in St. Marys, of which 29.0% had children under the age of 18 living in them. Of all households, 45.2% were married-couple households, 16.5% were households with a male householder and no spouse or partner present, and 32.9% were households with a female householder and no spouse or partner present. About 33.8% of all households were made up of individuals and 17.1% had someone living alone who was 65 years of age or older. of 2010, there were 1,860 people, 841 households, and 543 families living in the city. The population density was . There were 954 housing units at an average density of . The racial makeup of the city was 99.0% White, 0.1% African American, 0.2% Native American, 0.2% Asian, 0.1% from other races, and 0.4% from two or more races. Hispanic or Latino of any race were 1.3% of the population.
There were 841 households, of which 27.6% had children under the age of 18 living with them, 47.2% were married couples living together, 11.7% had a female householder with no husband present, 5.7% had a male householder with no wife present, and 35.4% were non-families. 31.2% of all households were made up of individuals, and 16% had someone living alone who was 65 years of age or older. The average household size was 2.21 and the average family size was 2.73.
The median age in the city was 43.9 years. 20.5% of residents were under the age of 18; 8% were between the ages of 18 and 24; 23.2% were from 25 to 44; 28.8% were from 45 to 64; and 19.5% were 65 years of age or older. The gender makeup of the city was 49.1% male and 50.9% female.
2000 census
As of the census