U.S. Route 1 or U.S. Highway 1 (US 1) is a major north–south United States Numbered Highway that serves the East Coast of the United States. It runs 2,370 miles (3,810 km) from Key West, Florida, north to Fort Kent, Maine, at the Canadian border, making it the longest north–south road in the United States. US 1 is generally paralleled by Interstate 95 (I-95), though US 1 is significantly farther west (inland) between Jacksonville, Florida, and Petersburg, Virginia, while I-95 is closer to the coastline. In contrast, US 1 in Maine is much closer to the coast than I-95, which runs farther inland than US 1. The route connects most of the major cities of the East Coast from the Southeastern United States to New England, including Miami, Jacksonville, Raleigh, Richmond, Washington D.C., Baltimore, Philadelphia, New York City, and Boston.
Interstate 95 (I-95) is the main north–south Interstate Highway on the East Coast of the United States, running from U.S. Route 1 (US 1) in Miami, Florida, north to the Houlton–Woodstock Border Crossing between Maine and the Canadian province of New Brunswick. The highway largely parallels the Atlantic coast and US 1, except for the portion between Savannah, Georgia, and Washington, D.C., and the portion between Portland and Houlton in Maine, both of which follow a more direct inland route.
Interstate 99 (I-99) is an Interstate Highway in the United States with two segments: one located in central Pennsylvania and the other in southern New York. The southern terminus of the route is near exit 146 of the Pennsylvania Turnpike (I-70/I-76) north of Bedford, where the road continues south as U.S. Route 220 (US 220). The northern terminus of the Pennsylvania segment is at exit 161 of I-80 near Bellefonte. The New York segment follows US 15 from the Pennsylvania–New York border to an interchange with I-86 in Corning. Within Pennsylvania, I-99 passes through Altoona and State College—the latter home to the Pennsylvania State University—and is entirely concurrent with US 220. Long-term plans call for the two segments of I-99 to be connected using portions of I-80, US 220, and US 15 through Pennsylvania.
Interstate 97 (I-97) is a north-south Interstate Highway in the eastern United States. It runs entirely within Anne Arundel County, Maryland for 17.62 miles (28.36 km) from U.S. Route 50/U.S. Route 301 (US 50/US 301) in Parole near Annapolis north to I-695 and I-895 in Brooklyn Park near Baltimore. The Interstate is the primary highway between Baltimore and Annapolis. I‑97 connects Annapolis with Baltimore/Washington International Airport and links the northern Anne Arundel County communities of Crownsville, Millersville, Severna Park, Glen Burnie, and Ferndale. It is the second shortest primary Interstate Highway after I-87 in North Carolina.
Route 21 is a state highway in northern New Jersey, running 14.35 mi (23.09 km) from the Newark Airport Interchange with U.S. Route 1/9 (US 1-9) and US 22 in Newark, Essex County to an interchange with US 46 in Clifton, Passaic County. The route is a four- to six-lane divided highway known as McCarter Highway on its southern portion in Newark that serves as a connector between the Newark and Paterson areas, following the west bank of the Passaic River for much of its length. It also serves as the main north–south highway through the central part of Newark, connecting attractions in Downtown Newark with Newark Airport. The portion of Route 21 through Newark is a surface arterial that runs alongside the elevated Northeast Corridor rail line through the southern part of the city and continues north through Downtown Newark while the portion north of Downtown Newark is a freeway. Route 21 intersects many major roads including Interstate 78 (I-78), Route 27, and I-280 in Newark, Route 7 in Belleville, and Route 3 in Clifton.
Interstate 83 (I-83) is an Interstate Highway located in the states of Maryland and Pennsylvania in the Eastern United States. Its southern terminus is at a signalized intersection with Fayette Street in Baltimore, Maryland; its northern terminus is at I-81 near Harrisburg, Pennsylvania. I-83 runs from Downtown Baltimore north to I-695 near the northern suburb of Timonium on the Jones Falls Expressway before forming a concurrency with I-695. After splitting from I-695, the route follows the Baltimore-Harrisburg Expressway north to the border between Maryland and Pennsylvania. Upon crossing the state line, I-83 becomes the Veterans of Foreign Wars of the United States Memorial Highway and continues north through York toward the Harrisburg area. The route runs along the southern and eastern portion of the Capital Beltway that encircles Harrisburg before reaching its northern terminus.
U.S. Route 111 (US 111) was a U.S. Highway that extended from Baltimore, Maryland north to the Harrisburg, Pennsylvania area. It replaced part of the Susquehanna Trail, partially signed as Pennsylvania Route 4, and was in turn replaced by Interstate 83 (I-83). Portions of its pre-freeway alignment are now Maryland Route 45 and I-83 Business. Other old sections in Pennsylvania are now unsigned Quadrant Routes or township-maintained roads. US 111 extended north to the Pennsylvania–New York state line where U.S. Route 15 now crosses it between 1928 and 1937.
U.S. Route 222 is a U.S. Highway that is a spur of US 22 in the states of Maryland and Pennsylvania. It runs for 95 miles (153 km) from US 1 in Conowingo, Maryland, north to Interstate 78 (I-78)/Pennsylvania Route 309 in Dorneyville, Pennsylvania. US 222 is almost entirely in Pennsylvania, and serves as the state's principal artery between the Lancaster and Reading areas and the Lehigh Valley.
Interstate 895 (I-895) is an auxiliary Interstate Highway in the US state of Maryland. Known as the Harbor Tunnel Thruway, the highway runs 11.44 miles (18.41 km) between one junction with I-95 in Elkridge and another interchange with I-95 on the east side of Baltimore. I-895 is a toll road that crosses the Patapsco River estuary via the Baltimore Harbor Tunnel, connecting U.S. Route 1 (US 1), I-695, and the Baltimore–Washington Parkway in the southwestern suburbs of Baltimore with US 40 on the east side of Baltimore. In conjunction with a pair of spurs, unsigned I-895A and I-895B, I-895 provides access to the tunnel from I-97 and Maryland Route 2 (MD 2) in Glen Burnie. The highway is designed for through traffic by having partial interchanges that require vehicles from almost all starting points to pass through the tunnel and the tunnel toll plaza, where a $4.00 toll is charged to passenger vehicles, before exiting the facility.
Interstate 695 (I-695) is a 51.46-mile-long (82.82 km) auxiliary Interstate Highway that is a full beltway extending around Baltimore, Maryland, United States. I-695 is officially designated the McKeldin Beltway but is colloquially referred to as either the Baltimore Beltway or 695. The route is an auxiliary route of I-95, intersecting that route southwest of Baltimore near Arbutus and northeast of the city near White Marsh. It also intersects other major roads radiating from the Baltimore area, including I-97 near Glen Burnie, the Baltimore–Washington Parkway near Linthicum, I-70 near Woodlawn, I-795 near Pikesville, and I-83 in the Timonium area. The 19.37-mile (31.17 km) portion of the Baltimore Beltway between I-95 northeast of Baltimore and I-97 south of Baltimore is officially Maryland Route 695 (MD 695) and is not part of the Interstate Highway System but is signed as I-695. This section of the route includes the Francis Scott Key Bridge that crosses over the Patapsco River. The bridge and its approaches are maintained by the Maryland Transportation Authority (MDTA) while the remainder of the Baltimore Beltway is maintained by the Maryland State Highway Administration (MDSHA).
Maryland Route 45 is a state highway in the U.S. state of Maryland. Known for most of its length as York Road, the state highway runs 30.06 miles (48.38 km) from U.S. Route 1 /US 40 Truck in Baltimore north to the Pennsylvania state line in Maryland Line, where the highway continues as State Route 3001. MD 45 is the primary highway between Downtown Baltimore and Towson, the county seat of Baltimore County. North of Interstate 695 (I-695), the state highway parallels I-83 and serves the suburban communities of Lutherville, Timonium, Cockeysville, and Hunt Valley. MD 45 also connects the northern Baltimore County communities of Hereford and Parkton. The state highway is maintained by the Maryland State Highway Administration in Baltimore County and by the Baltimore City Department of Transportation in the city, where the highway also follows Greenmount Avenue.
Interstate 684 (I-684) is a 28.47-mile-long (45.82 km) north–south auxiliary Interstate Highway in the state of New York in the United States. There is also a short portion in Connecticut with no junctions. The highway connects I-84 with I-287 and the Hutchinson River Parkway, primarily serving commuter traffic to and from the northern suburbs of the New York metropolitan area. Most of the route is in northern Westchester County. The route of the highway was originally designated as part of I-87 from 1968 to 1970. The first section of the roadway opened to traffic in October 1968, and the final segment was completed in December 1974.
Interstate 395 (I-395) is an auxiliary Interstate Highway in the US state of Maryland. Known as Cal Ripken Way, the highway runs 1.98 miles (3.19 km) from I-95 north to Howard Street and Camden Street in Downtown Baltimore, where it provides access to the Inner Harbor and the Baltimore Convention Center. The Interstate also serves the Camden Yards Sports Complex, which contains M&T Bank Stadium and Oriole Park at Camden Yards, homes of the Baltimore Ravens and Baltimore Orioles, respectively. I-395 also serves as the southern terminus of Martin Luther King Jr. Boulevard, an urban arterial that provides a western bypass of Downtown Baltimore and connects I-95 with U.S. Route 40 (US 40), US 1, and I-83. The Interstate is maintained by the Maryland Transportation Authority (MDTA) and, like all Interstates, is a part of the National Highway System.
Interstate 78 (I-78) is an east–west route stretching from Union Township, Lebanon County, Pennsylvania, to New York City. In New Jersey, I-78 is called the Phillipsburg–Newark Expressway and the Newark Bay–Hudson County Extension of the New Jersey Turnpike. The highway runs for 67.83 miles (109.16 km) in the northern part of the state of New Jersey from the I-78 Toll Bridge over the Delaware River at the Pennsylvania state line in Phillipsburg, Warren County, east to the Holland Tunnel under the Hudson River at the New York state line in Jersey City, Hudson County. The Phillipsburg–Newark Expressway portion of I-78, formally called the Lightning Division Memorial Highway, runs from the Phillipsburg area east across rural areas of western New Jersey before entering suburban areas in Somerset County. The road crosses the Watchung Mountains, widening into a local–express lane configuration at Route 24 as it continues through urban areas to Newark. Here, I-78 intersects the mainline of the New Jersey Turnpike (I-95) and becomes the Newark Bay Extension, crossing the Newark Bay Bridge and continuing to Jersey City. The route, along with Route 139, follows a one-way pair of surface streets to the Holland Tunnel.
U.S. Route 50 is a major east–west route of the U.S. Highway system, stretching just over 3,000 miles (4,800 km) from West Sacramento, California, east to Ocean City, Maryland, on the Atlantic Ocean. In the U.S. state of Maryland, US 50 exists in two sections. The longer of these serves as a major route connecting Washington, D.C., with Ocean City; the latter is the eastern terminus of the highway. The other section passes through the southern end of Garrett County for less than 10 miles (16 km) as part of the Northwestern Turnpike, entering West Virginia at both ends. One notable section of US 50 is the dual-span Chesapeake Bay Bridge across the Chesapeake Bay, which links the Baltimore–Washington metropolitan area with the Eastern Shore region, allowing motorists to reach Ocean City and the Delaware Beaches.
Interstate 95 (I-95) is an Interstate Highway running along the East Coast of the United States from Miami, Florida, north to the Canadian border in 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.
Pennsylvania Route 283 (PA 283), officially State Route 0300 or SR 0300 due to the presence of Interstate 283 (I-283), is a 29-mile-long (47 km) state highway in the U.S. state of Pennsylvania. A freeway for nearly its entire length, it connects Harrisburg to Lancaster, paralleling the old U.S. Route 230. The route follows a generally northwest–southeast direction and is signed east–west. The number was assigned based on the function the route serves as a southeastern extension of I-283, but I-283 and PA 283 are not the same roadway; the two intersect at a partial cloverleaf interchange.
Interstate 70 (I-70) is a part of the Interstate Highway System that runs from Cove Fort, Utah, to Baltimore, Maryland. In Maryland, the Interstate Highway runs 93.62 miles (150.67 km) from the Pennsylvania state line in Hancock east to the Interstate's eastern terminus near its junction with I-695 at a park and ride in Baltimore. I-70 is the primary east–west Interstate in Maryland; the Interstate Highway connects Baltimore—and Washington, D.C., via I-270—with Western Maryland. The Interstate serves Frederick and Hagerstown directly and provides access to Cumberland via its junction with I-68 at Hancock. I-70 runs concurrently with its predecessor highway, U.S. Route 40 (US 40), from Hancock to Indian Springs in Washington County and from Frederick to West Friendship in Howard County.
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.
Maryland Route 137 is a state highway in the U.S. state of Maryland. Known as Mount Carmel Road, the state highway runs 8.50 miles (13.68 km) from Gunpowder Road near Hampstead east to MD 45 at Hereford in northern Baltimore County. MD 137 was built in the early 1920s.
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