Maryland Route 7 (MD 7) is a collection of state highways in the U.S. state of Maryland. Known for much of their length as Philadelphia Road, there are five disjoint mainline sections of the highway totaling 40.23 miles (64.74 km) that parallel U.S. Route 40 (US 40) in Baltimore, Harford, and Cecil counties in northeastern Maryland. The longest section of MD 7 begins at US 40 just east of the city of Baltimore in Rosedale and extends through eastern Baltimore County and southern Harford County to US 40 in Aberdeen. The next segment of the state highway is a C-shaped route through Havre de Grace on the west bank of the Susquehanna River. The third mainline section of MD 7 begins in Perryville on the east bank of the Susquehanna River and ends at US 40 a short distance west of the start of the fourth section, which passes through Charlestown and North East before ending at US 40, just west of Elkton. The fifth segment of the highway begins at South Street and passes through the eastern part of Elkton before reconnecting with US 40 east of Elkton and west of the Delaware state line.

U.S. Route 40 in the U.S. state of Maryland runs from Garrett County in Western Maryland to Cecil County in the state's northeastern corner. With a total length of 221 miles (356 km), it is the longest numbered highway in Maryland. Almost half of the road overlaps or parallels with Interstate 68 (I-68) or I-70, while the old alignment is generally known as US 40 Alternate, US 40 Scenic, or Maryland Route 144. West of Baltimore, in the Piedmont and Appalachian Mountains / Blue Ridge region of the Western Maryland panhandle of the small state, the portions where it does not overlap an Interstate highway are mostly two-lane roads. The portion northeast of Baltimore going toward Wilmington in northern Delaware and Philadelphia in southeastern Pennsylvania is a four-lane divided highway, known as the Pulaski Highway. This section crosses the Susquehanna River at the north end of the Chesapeake Bay on the Thomas J. Hatem Memorial Bridge.