San Mar, Maryland
San Mar is a census-designated place (CDP) in Washington County, Maryland, United States. The population was 515 at the 2000 census. History Mannheim was listed on the National Register of Historic Places in 1979. Geography San Mar is located at (39.551764, −77.646241). According to the United States Census Bureau, the CDP has a total area of , all land. Demographics As of the census of 2000, there were 515 people, 167 households, and 108 families residing in the CDP. The population density was . There were 178 housing units at an average density of . The racial makeup of the CDP was 98.83% White, 0.58% African American, 0.19% Native American, 0.19% Asian, and 0.19% from two or more races. Hispanic or Latino of any race were 0.19% of the population. There were 167 households, out of which 21.6% had children under the age of 18 living with them, 59.9% were married couples living together, 1.8% had a female householder with no husband present, and 35.3% were non-families. 28.7% of all households were made up of individuals, and 22.8% had someone living alone who was 65 years of age or older. The average household size was 2.32 and the average family