Maryland Route 648 is a collection of state highways in the U.S. state of Maryland. These nine highways are current or former sections of the Baltimore–Annapolis Boulevard between Annapolis and Baltimore via Glen Burnie. There are five signed mainline segments of MD 648 through Arnold, Severna Park, Pasadena, Glen Burnie, Ferndale, and Pumphrey in northern Anne Arundel County; Baltimore Highlands in southern Baltimore County; and the independent city of Baltimore. MD 648 mainly serves local traffic along its meandering route, with long-distance traffic intended to use the parallel and straighter MD 2 south of Glen Burnie and freeway-grade Interstate 97 (I-97), I-695, and MD 295 between Glen Burnie and Baltimore.

Baltimore Highlands is a census-designated place (CDP) in Baltimore County, Maryland, United States, directly south of the city of Baltimore. The population was 7,019 at the 2010 census. At the 2000 census and earlier, the area was delineated as part of the Lansdowne-Baltimore Highlands CDP.