The Maryland Transit Administration (MTA) operates three rail systems—one light rail, one rapid transit, and one commuter rail—in the Baltimore area; all three systems have stations in Baltimore County. The heavy-rail Metro SubwayLink runs northwest of the city to Owings Mills; the Light RailLink system runs north of Baltimore City to Hunt Valley and south of the city through Baltimore Highlands with some routes terminating at Baltimore/Washington International Thurgood Marshall Airport, Maryland. Commuter MARC Train service is available in the county at Halethorpe, St. Denis, and Martin State Airport stations. The MTA's local and regional bus services also serve Baltimore County. Rail Both CSX Transportation and Amtrak mainlines run through the county. Former rail lines running through the County beginning in the 19th Century were the Maryland and Pennsylvania Railroad (MPR) and the Northern Central Railway (previously the Baltimore and Susquehanna Railroad, later becoming part of the old Pennsylvania Railroad). MPR and parts of the Northern Central were abandoned. The present-day streetcar/trolley line coming north from Anne Arundel County and the International Airport through Baltimore City uses the Northern Central right-of-way south of Cockeysville and Timonium; starting slightly north of that, the right-of-way was converted into the popular hiking, biking and jogging pathway from Loch Raven to the Mason–Dixon line with Pennsylvania known now as the Torrey C. Brown Rail Trail, named for a former state secretary of natural resources. Demographics 2020 census Note: the US Census treats Hispanic/Latino as an ethnic category. This table excludes Latinos from the racial categories and assigns them to a separate category. Hispanics/Latinos can be of any race. 2010 census As of the 2010 United States Census, 805,029 people, 316,715 households, and 205,113 families resided there. The population density was . The 335,622 housing units supported an average density of . The racial makeup of the county was 64.6% white, 26.1% black or African American, 5.0% Asian, 0.3% American Indian, 1.6% from other races, and 2.4% from two or more races. Those of Hispanic or Latino origin made up 4.2% of the population. In terms of ancestry, 20.7% were German, 14.6% were Irish, 8.7% were English, 7.4% were Italian, 5.8% were Polish and 5.0% were American. Of the 316,715 households, 31.4% had children under the age of 18 living with them, 45.5% were married couples living together, 14.5% had a female householder with no husband present, 35.2% were non-families, and 28.3% of all households