Interstate 95 (I-95) is an Interstate Highway running along the East Coast of the United States from Miami, Florida, north to the Canada–United States border at Houlton, Maine. In Maryland, the route is a major highway that runs 110.01 miles (177.04 km) diagonally from southwest to northeast, entering from the District of Columbia and Virginia at the Woodrow Wilson Bridge over the Potomac River, northeast to Maryland's border with Delaware near Elkton. It is the longest Interstate Highway within Maryland and is one of the most traveled Interstate Highways in the state, especially between Baltimore and Washington, D.C., despite alternate routes along the corridor, such as the Baltimore–Washington Parkway, U.S. Route 1 (US 1), and US 29. I-95 also has eight auxiliary routes in the state, the most of any state along the I-95 corridor. Portions of the highway, including the Fort McHenry Tunnel and the Millard E. Tydings Memorial Bridge, are tolled.

U.S. Route 29 (US 29) is a north–south United States Numbered Highway that runs for 1,043.3 miles (1,679.0 km) from Pensacola, Florida, to the western suburbs of Baltimore, Maryland. In the U.S. state of Maryland, US 29 is a major highway that emerges from Washington DC and runs north into eastern Montgomery County, stretching over 25.86 miles (41.62 km) through the state and terminating at Maryland Route 99 (MD 99) outside of Ellicott City. It serves the cities of Columbia and Ellicott City and provides the westernmost north–south route between Washington DC and Baltimore.