Maryland Road Map

Interstate and U.S. State Highways of Maryland

Maryland has one of the most complex and heavily traveled highway networks on the U.S. East Coast. Despite its small size, the state serves as a critical transportation hub between the Northeast, the Mid-Atlantic, and the South. Its system of Interstate highways, U.S. highways, and state highways connects major cities like Baltimore and Washington, D.C. suburbs to rural communities on the Eastern Shore, in Western Maryland, and in southern counties along the Chesapeake Bay.

Overview of Maryland’s Highway System

Maryland’s highway system is administered primarily by the Maryland Department of Transportation State Highway Administration (MDOT SHA), with key urban toll facilities operated by the Maryland Transportation Authority (MDTA) and certain county and municipal routes maintained locally. The system consists of:

• Interstate Highways: Major freeways forming part of the federal Interstate Highway System.
• U.S. Highways: Numbered routes of the national U.S. Highway System, predating the Interstates.
• Maryland State Highways: State-designated routes (MD 2, MD 32, etc.) that fill gaps between Interstates and U.S. highways and provide regional and local connectivity.
• Toll Facilities: Bridges, tunnels, and expressways primarily under MDTA (e.g., I‑95 JFK Highway, Fort McHenry and Harbor tunnels, Bay Bridge).

The geometric diversity of Maryland—from mountains in the west to coastal plains on the Eastern Shore—has shaped how its highways developed, with major corridors following historic trade routes, rail lines, and river crossings.

Numbering and Classification Principles

Interstate Highway Numbering

Maryland’s Interstate highways follow the national numbering conventions:

• Primary Interstates (one- or two-digit): East–west routes have even numbers (e.g., I‑68, I‑70, I‑66), and north–south routes have odd numbers (e.g., I‑81, I‑83, I‑95, I‑97).
• Auxiliary Interstates (three-digit): Spur or loop routes connect primary Interstates to cities, airports, or bypasses. The last two digits reference the parent Interstate (e.g., I‑195 and I‑395 connect to I‑95; I‑270 connects to I‑70).
• Beltways and circumferential routes: Typically have an even first digit (e.g., I‑495 around Washington, D.C.).

U.S. Highway Numbering

Maryland’s U.S. highways predate the Interstate system and connect across state lines:

• East–west U.S. routes: Even-numbered, with numbers increasing from north to south (e.g., US 40, US 50).
• North–south U.S. routes: Odd-numbered, with numbers increasing from east to west (e.g., US 1, US 13, US 29, US 301).

Maryland State Highway Numbering

Maryland state routes use “MD” followed by a number (e.g., MD 2, MD 32). The numbering system is not strictly grid-based, but there are patterns:

• Low numbers (MD 2–MD 5): Typically older, long-distance routes that predate modern freeways.
• Two- and three-digit routes: Used extensively for regional connectors, suburban arterials, and rural corridors.
• 600s and higher in some areas: Sometimes used for shorter connectors, spurs, and former segments of older highways.

Over time, segments of U.S. or state highways have been relocated, widened, or bypassed, leaving behind “Old” alignments that may still carry local road names (e.g., Old National Pike, Old Annapolis Road) alongside the newer mainline route.

Interstate Highways in Maryland

Maryland’s Interstate system comprises multiple primary and auxiliary routes that serve regional, interstate, and commuter traffic. The network is anchored by I‑95, the busiest north–south freeway on the East Coast, and I‑70 / I‑68, which connect the Baltimore–Washington region with the Appalachian interior and the Midwest.

Primary Interstate Routes

• I‑68 (National Freeway)
  

  I‑68 runs entirely through Western Maryland (and briefly West Virginia at its western end), connecting I‑79 in West Virginia to I‑70 near Hancock, Maryland. It follows a corridor historically served by the National Road and U.S. 40. The route:

  • Serves Cumberland and Frostburg and provides the primary east–west freeway across the Allegheny Mountains in Maryland.
  • Improves access to recreation areas such as Deep Creek Lake and the greater Appalachian region.
  • Includes steep grades and mountainous terrain, making it operationally distinct from flatter routes in central and eastern Maryland.
• I‑70
  

  I‑70 is Maryland’s principal west–east Interstate across central Maryland, entering from Pennsylvania near Hancock and ending in Baltimore. It:

  • Aligns closely with the historic National Road and U.S. 40.
  • Connects Hagerstown, Frederick, and the western suburbs of Baltimore.
  • Intersects I‑68, I‑81, I‑270, and I‑695, serving long-distance, commuter, and freight traffic.
  • Terminates near the Baltimore Beltway; an originally planned extension into downtown Baltimore was never fully completed, leaving a short stub and local ramps near the city.
• I‑81
  

  I‑81 clips the extreme western part of Maryland in Washington County near Hagerstown. Although short within Maryland, it is part of a major north–south inland freight corridor extending from Tennessee to New York. In Maryland:

  • I‑81 interchanges with I‑70 near Hagerstown.
  • Supports high volumes of truck traffic and distribution centers in the Hagerstown area.
  • Provides an alternative to I‑95 for long-haul traffic avoiding coastal congestion.
• I‑83
  

  I‑83 links Baltimore with Harrisburg, Pennsylvania. In Maryland, it is known as the Jones Falls Expressway (JFX) within Baltimore. The route:

  • Begins near downtown Baltimore and runs north through the city and Baltimore County.
  • Follows the Jones Falls valley, with a combination of elevated and depressed sections.
  • Serves daily commuters between Baltimore and northern suburbs such as Timonium, Cockeysville, and Hunt Valley, then continues to York and Harrisburg, PA.
• I‑95
  

  I‑95 is the backbone of Maryland’s Interstate network, carrying dense commuter and freight traffic between Washington, D.C., Baltimore, Wilmington, Philadelphia, New York, and beyond. Key Maryland characteristics include:

  • Capital Beltway Segment: Shared with I‑495 around the Washington, D.C. metropolitan area in Prince George’s and Montgomery counties.
  • Baltimore–Washington Corridor: A heavily traveled, multi-lane section connecting the Capital Beltway to the Baltimore Beltway, with numerous interchanges serving suburbs and employment centers.
  • Baltimore Region: North of I‑695, I‑95 includes the Fort McHenry Tunnel segment under Baltimore Harbor (an MDTA toll facility).
  • Northeastern Maryland: The JFK Memorial Highway segment between the Baltimore area and Delaware, also a toll facility and a critical freight corridor.
• I‑97
  

  I‑97 is entirely within Maryland and among the shortest primary Interstates in the country. It connects the Baltimore–Annapolis corridor:

  • Runs from I‑695 near Baltimore to US 50/US 301 near Annapolis.
  • Serves as the main freeway link between the Baltimore area and the state capital.
  • Superseded portions of MD 3 and MD 32 when constructed and upgraded.

Interstate Beltways and Auxiliary Routes

• I‑495 (Capital Beltway)
  

  I‑495 encircles Washington, D.C. through both Maryland and Virginia, functioning as a regional beltway and interstate gateway. In Maryland:

  • Passes through Montgomery and Prince George’s counties.
  • Is concurrent with I‑95 along the eastern side of the loop.
  • Connects to I‑270, I‑295 (in D.C.), and numerous major arterials serving suburban communities such as Bethesda, Silver Spring, College Park, and Greenbelt.
  • Experiences chronic congestion, prompting managed lane, interchange reconstruction, and transit-coordination studies over time.
• I‑695 (Baltimore Beltway)
  

  I‑695 forms a complete loop around Baltimore City and is one of Maryland’s busiest highways. It:

  • Circles through Baltimore County and touches Anne Arundel County near its southern arc.
  • Connects with I‑70, I‑83, I‑95, I‑97, and major radial state highways (e.g., MD 2, MD 45, MD 140, MD 295).
  • Includes a mix of older, narrow sections and extensively reconstructed modern segments to handle high traffic volumes.
• I‑270
  

  I‑270 is the primary freeway tying the I‑70 corridor to the Washington, D.C. region. The route:

  • Begins in Frederick (splitting from I‑70) and runs south through Urbana, Clarksburg, Germantown, Gaithersburg, and Rockville.
  • Transitions into I‑270 Spur toward the Capital Beltway, serving as a commuter corridor for Montgomery County residents.
  • Supports major employment centers in the “I‑270 Technology Corridor,” including biotech, defense, and tech firms.
  • Has been studied extensively for congestion relief, including HOV, managed lanes, and transit integration.
• I‑195
  

  I‑195 is a short but important connector freeway near Baltimore. It:

  • Runs between I‑95 and MD 295 (Baltimore–Washington Parkway) and the entrance to Baltimore/Washington International Thurgood Marshall Airport (BWI).
  • Provides primary freeway access to BWI, one of the region’s major airports.
  • Serves both passenger and cargo operations via dedicated ramps to airport terminals and nearby business parks.
• I‑270 Spur
  

  The I‑270 Spur branches south from the main I‑270 near Rockville and:

  • Connects directly to the I‑495 (Capital Beltway) western segment.
  • Facilitates movement between northern Montgomery County and Virginia-bound traffic via the American Legion Bridge.
• I‑370
  

  I‑370 is a short connector in Montgomery County:

  • Links I‑270 near Gaithersburg to MD 200 (Intercounty Connector) and the Shady Grove area.
  • Provides access to park-and-ride facilities and the Washington Metro’s Red Line terminus at Shady Grove.
• I‑395 (Baltimore)
  

  I‑395 in Baltimore is a downtown spur of I‑95:

  • Extends from I‑95 into the heart of downtown Baltimore.
  • Provides access to the Inner Harbor, Camden Yards, M&T Bank Stadium, and central business districts.
  • Is heavily used for event traffic and daily commuting.
• I‑495 / I‑95 concurrency
  

  In Maryland, I‑95 and I‑495 run together along the eastern side of the Capital Beltway:

  • This concurrency is often simply referred to as “the Beltway” by local drivers.
  • The segment includes key interchanges with US 1, MD 295 (via nearby connectors), and MD 4 / MD 5 corridors.

U.S. Highways in Maryland

U.S. highways in Maryland provide essential long-distance and regional routes that complement the Interstate system. Many pass directly through older downtowns, reflecting their origins before limited-access freeways were constructed.

Major North–South U.S. Highways

• US 1
  

  US 1 parallels I‑95 through Maryland but typically runs closer to older commercial strips and downtown areas. It:

  • Enters from the District of Columbia at the southern end and continues through Prince George’s County, including College Park and Laurel, into Howard and Baltimore counties.
  • Passes near major institutions such as the University of Maryland, College Park.
  • Continues through Baltimore City and northeast toward Harford County and the Susquehanna River.
  • Serves local and regional traffic with signalized intersections and commercial frontage development.
• US 13
  

  US 13 traverses Maryland’s Eastern Shore, forming part of a major corridor running from North Carolina to Delaware and beyond. In Maryland:

  • Runs through Wicomico and Somerset counties, including Salisbury, a regional economic hub.
  • Connects to US 50 near Salisbury, facilitating travel toward Ocean City and the Chesapeake Bay Bridge.
  • Continues north into Delaware and eventually to Pennsylvania.
• US 15
  

  US 15 runs along Maryland’s western edge, serving as:

  • A key north–south corridor through Frederick County, connecting to Virginia to the south and Pennsylvania to the north.
  • An important freight and commuter route that intersects with I‑70 and I‑270 near Frederick.
  • A link between the Washington metropolitan region and areas such as Gettysburg, PA.
• US 29
  

  US 29 in Maryland is a heavily used commuter artery between Silver Spring and Columbia:

  • Starts at the District of Columbia line in Montgomery County and proceeds north through Silver Spring.
  • Becomes a limited-access freeway for much of its length in Howard County, serving Columbia and Ellicott City.
  • Connects to I‑70 and continues into central Maryland farmland before entering Pennsylvania.
• US 301
  

  US 301 provides an important alternative to I‑95, particularly for traffic between the Washington–Baltimore region and Virginia / the Southeast. In Maryland:

  • Enters from Virginia across the Potomac River via the Governor Harry W. Nice Memorial / Senator Thomas “Mac” Middleton Bridge in Charles County.
  • Runs north through Southern Maryland and Prince George’s County.
  • Is concurrent with US 50 east of the Chesapeake Bay, serving as a high-speed corridor across the Eastern Shore toward Delaware.

Major East–West U.S. Highways

• US 40
  

  US 40 is one of Maryland’s most historically significant routes, following the path of the National Road and serving major cities:

  • Runs from Western Maryland through Hagerstown, Frederick, and into the Baltimore region.
  • Parallels I‑70 in central Maryland and I‑68 further west, often serving as a local frontage or alternate route.
  • Continues east through Baltimore City and then northeast toward Harford and Cecil counties.
  • Includes historic segments that became local roads when newer freeway bypasses were constructed.
• US 50
  

  US 50 is a major transcontinental route whose Maryland segment has both urban and resort-oriented functions. It:

  • Enters Maryland from Washington, D.C. and becomes a major freeway through Prince George’s and Anne Arundel counties, passing near Annapolis.
  • Crosses the Chesapeake Bay via the William Preston Lane Jr. Memorial Bay Bridge (a critical toll facility).
  • Continues across the Eastern Shore, serving Cambridge, Salisbury (where it intersects US 13), and finally Ocean City on the Atlantic coast.
  • Is concurrent with US 301 from the Bay Bridge area to Queenstown before diverging toward Ocean City.

Other Key U.S. Highways in Maryland

• US 220
  

  US 220 enters Western Maryland near Cumberland and:

  • Connects Cumberland with West Virginia to the south.
  • Interacts with I‑68 and provides access to Appalachian communities.
• US 340
  

  US 340 serves as a regional connector in western Maryland:

  • Runs from Frederick southwest through Jefferson County, West Virginia, and into Virginia.
  • Connects the Frederick area with Harpers Ferry, WV, and the Shenandoah Valley.
• US 522
  

  US 522 has a brief presence in far Western Maryland around Hancock:

  • Intersects with I‑70 and I‑68 near the narrow “waist” of Maryland.
  • Links Hancock with West Virginia and Pennsylvania.

Maryland State Highways: Structure and Function

Maryland’s state highway network ranges from high-speed expressways to two-lane rural roads. These routes fill the gaps between Interstate and U.S. highways, supporting local economies, tourism, and daily commuting.

Characteristics of State Routes

• Designation: Labeled as “MD” followed by a number (e.g., MD 2, MD 32, MD 198). Signage typically uses a white shield with black numerals.
• Jurisdiction: Most are maintained by MDOT SHA, though some segments may be municipally maintained within city limits.
• Functional types:
  • Four- to six-lane divided highways in suburban corridors.
  • Two-lane rural connectors across agricultural and forested regions.
  • Urban arterials and “main streets” in small towns and city neighborhoods.

Notable State Highway Corridors

• MD 2
  

  MD 2 is a long north–south corridor linking Baltimore and Annapolis with communities in Anne Arundel and Calvert counties. It:

  • Runs through the Baltimore area (often paired as MD 2/MD 3 or along Governor Ritchie Highway in older segments).
  • Continues south through suburban and semi-rural communities toward Solomons Island in Calvert County.
  • Provides an alternative to I‑97 and US 50/301 for local travel.
• MD 3
  

  MD 3 historically connected Baltimore and Washington before I‑97 and other freeways assumed much of that role. Today it:

  • Functions primarily as a suburban arterial in Anne Arundel County.
  • Links to US 50/301 near Bowie, facilitating regional travel.
• MD 4
  

  MD 4 is a major expressway from southern Maryland toward the Capital Beltway. It:

  • Runs from Calvert County (near Solomons) north through Prince Frederick and Dunkirk into Prince George’s County.
  • Becomes a multi-lane, divided expressway closer to the Washington metropolitan area.
  • Intersects with I‑95/I‑495 near the District of Columbia, providing an important commuter route for southern Maryland residents.
• MD 5
  

  MD 5 is another major southern Maryland corridor:

  • Connects Waldorf, Charles County, and St. Mary’s County with the Washington region.
  • Includes expressway segments (e.g., Branch Avenue Expressway) approaching the Capital Beltway.
  • Serves military installations and defense-industry employers in the region.
• MD 32
  

  MD 32 is a critical east–west freeway/expressway in central Maryland:

  • Runs from I‑70 near West Friendship through Howard County and Fort Meade to MD 97 / US 301 near Annapolis and Bowie areas.
  • Provides direct access to Fort George G. Meade, NSA, and major technology / cybersecurity campuses.
  • Serves as a commuter route between Howard/Anne Arundel counties and both Baltimore and Washington corridors.
• MD 45
  

  MD 45 is the former route of US 111 and closely parallels I‑83:

  • Known locally as York Road, running from Baltimore City north through Towson, Timonium, and into northern Baltimore County.
  • Serves as a busy urban and suburban commercial corridor with heavy local traffic.
• MD 97
  

  MD 97 runs north–south between the Washington suburbs and central Maryland farmland:

  • Extends from near the District of Columbia through Silver Spring and Wheaton, then north through Olney, Brookeville, and Westminster.
  • Provides a direct link between the Capital Beltway area and Carroll County.
• MD 100
  

  MD 100 is a key east–west expressway in Anne Arundel and Howard counties:

  • Connects US 29 and I‑95 near Ellicott City to MD 177 near Pasadena.
  • Intersects I‑97 and MD 295, providing an important route between suburban employment centers, BWI area, and residential communities.
• MD 200 (Intercounty Connector, ICC)
  

  MD 200 is a modern, all-electronic toll freeway connecting Montgomery and Prince George’s counties:

  • Links I‑370 and I‑270 near Gaithersburg with I‑95 near Laurel / Beltsville.
  • Provides an east–west alternative to local arterials like MD 28 and MD 198, reducing travel times between I‑270 and I‑95.
  • Uses open-road tolling technology with no traditional toll plazas.
• MD 295 (Baltimore–Washington Parkway)
  

  While portions of the Baltimore–Washington Parkway are federally maintained as a parkway, MD 295 designates the state-maintained segment:

  • Runs between Baltimore and the Washington metropolitan area.
  • Serves as a scenic, limited-access alternative to I‑95 and US 1.
  • Provides access to BWI and numerous federal and private employment sites.
• MD 404
  

  MD 404 is a crucial Eastern Shore corridor connecting the Chesapeake Bay Bridge area to Delaware and Atlantic beaches:

  • Serves as a main route for seasonal beach traffic heading toward Ocean City, Rehoboth Beach, and other coastal destinations.
  • Has undergone widening and safety improvements to accommodate heavy summer traffic volumes and reduce crash risks.

Toll Bridges, Tunnels, and Key Crossings

Maryland’s geography—dominated by the Chesapeake Bay and numerous rivers—requires major highway crossings that are often tolled and critical to regional mobility.

Chesapeake Bay and Harbor Crossings

• William Preston Lane Jr. Memorial (Chesapeake Bay) Bridge
  

  Carrying US 50/US 301, this dual-span bridge connects Anne Arundel County (western shore) and Queen Anne’s County (Eastern Shore). It:

  • Is the primary road link between the Baltimore–Washington region and the Eastern Shore / Ocean City.
  • Carries substantial tourist traffic, particularly in summer months.
  • Operates as a tolled facility managed by MDTA.
• Fort McHenry Tunnel (I‑95)
  

  The Fort McHenry Tunnel carries I‑95 under Baltimore Harbor:

  • Bypasses downtown Baltimore and provides a direct I‑95 route through the region.
  • Is tolled and managed by MDTA.
  • Is designed to accommodate high traffic volumes while protecting the historically significant site of Fort McHenry above.
• Baltimore Harbor Tunnel (I‑895)
  

  I‑895, a parallel toll route to I‑95, includes the Baltimore Harbor Tunnel:

  • Provides an alternative harbor crossing for through traffic.
  • Helps distribute traffic load between two major underwater crossings in Baltimore.

Other Significant Crossings

• Governor Harry W. Nice Memorial / Senator Thomas “Mac” Middleton Bridge (US 301)
  

  This bridge spans the Potomac River between Charles County, Maryland, and King George County, Virginia:

  • Carries US 301 as a major alternative to I‑95 for regional traffic.
  • Functions as a tolled facility with a strategic role in freight and long-distance travel.
• Interstate River Crossings in Western Maryland
  

  Several Interstate and U.S. highway bridges cross the Potomac and other rivers in Western Maryland:

  • Connect Maryland to West Virginia and Virginia at key points like I‑81 and US 15.
  • Support both regional commuting and through freight traffic.

Regional Roles of Maryland Highways

Maryland’s highway network plays distinct roles in different regions of the state, shaped by population density, economic activity, and natural geography.

Baltimore Region

• Core Interstates: I‑95, I‑83, I‑70, I‑97, and I‑695 form the backbone of metropolitan mobility.
• Urban Access: I‑395 and various state highways (e.g., MD 2, MD 295, MD 45) funnel traffic into downtown and harbor areas.
• Freight: The port of Baltimore and local distribution centers rely heavily on I‑95, I‑695, and US 40 for truck movements.

Washington, D.C. Suburbs in Maryland

• Beltway and spurs: I‑495, I‑95, and I‑270 support intense commuter flows between Maryland suburbs, the District, and Virginia.
• Radial state routes: MD 4, MD 5, MD 97, MD 295, and MD 355 serve dense residential and employment corridors.
• East–west connectors: MD 200 (ICC), MD 28, and MD 198 aim to reduce local congestion and offer alternatives to surface streets.

Eastern Shore

• Tourism and agriculture: US 50, US 13, US 301, and MD 404 connect farms, small towns, and beach destinations.
• Bay Bridge dependency: Seasonal traffic peaks are strongly tied to the capacity of US 50/301 and the Chesapeake Bay Bridge.

Western Maryland

• Mountain corridors: I‑68, I‑70, US 40, and US 220 support regional commerce and long-distance trucking.
• Recreation access: Highways provide access to state parks, ski areas, and outdoor recreation in Allegany and Garrett counties.

Safety, Operations, and Modernization

Maryland continuously invests in its highway network to address congestion, safety, and resilience. Efforts include:

• Capacity projects: Adding auxiliary lanes, reconfiguring interchanges, and implementing managed lanes on heavily traveled corridors such as I‑95, I‑270, and segments of I‑695 and I‑495.
• Safety improvements: Median barriers, upgraded guardrails, improved lighting, and roundabouts on rural and suburban state highways.
• Intelligent Transportation Systems (ITS): Real-time traffic monitoring, variable message signs, ramp metering (where applicable), and coordinated incident response on major Interstates and arterials.
• Asset management: Ongoing pavement rehabilitation, bridge inspection and repair, and tunnel maintenance on key structures such as the Bay Bridge and harbor tunnels.

Traveler Information and Practical Use

For drivers, understanding how Maryland’s Interstate, U.S., and state highways fit together helps in route planning:

• Long-distance north–south travel: Typically uses I‑95 or US 301, with I‑81 as an inland alternative and US 13 on the Eastern Shore.
• East–west cross-state travel: Relies on I‑70 and I‑68 in the west and US 50/US 40 across central and eastern regions.
• Commuter movement: Centers on the beltways (I‑495, I‑695), I‑270, MD 295, MD 32, MD 100, and similar expressways.
• Beach and tourism routes: Focus on US 50/US 301 to the Eastern Shore, then US 50, US 13, and MD 404 toward Atlantic beaches.

As Maryland continues to grow and evolve, its system of Interstates, U.S. highways, and state routes remains fundamental to the state’s economy, daily life, and connections to the broader Mid-Atlantic and national transportation networks.