Located on the eastern seaboard of the US in the South Atlantic region, Maryland ranks 42nd in size among the 50 states.
Maryland's total area—10,460 sq mi (27,092 sq km)—comprises 9,837 sq mi (25,478 sq km) of land and 623 sq mi (1,614 sq km) of inland water. The state extends 199 mi (320 km) E-W and 126 mi (203 km) N-S.
Maryland is bordered on the N by Pennsylvania; on the E by Delaware and the Atlantic Ocean; on the S and SW by Virginia, the District of Columbia, and West Virginia (with the line passing through the Chesapeake Bay and Potomac River); and on the extreme W by West Virginia. Important islands in Chesapeake Bay, off Maryland's Eastern Shore (the Maryland sector of the Delmarva Peninsula), include Kent, Bloodsworth, South Marsh, and Smith.
The total boundary length of Maryland is 842 mi (1,355 km), including a general coastline of 31 mi (50 km); the total tidal shoreline extends 3,190 mi (5,134 km). The state's geographic center is in Prince George's County, 4.5 mi (7.2 km) NW of Davidsonville.