Route 40 (US 40)

Route 40 (US 40)
Country	USA
Type	US
Route	40
Length mi	2865
Established	1926
Direction a	West
Terminus a	near Park City, Utah
Direction b	East
Terminus b	Atlantic Ocean at Atlantic City, New Jersey
States	Utah, Colorado, Kansas, Missouri, Illinois, Indiana, Ohio, West Virginia, Maryland, Pennsylvania, Delaware, New Jersey

Route 40 (US 40) is a major east–west United States Numbered Highway that traverses the country from the Rocky Mountains to the Atlantic Ocean. It links mountain passes, plains, industrial centers, historic towns, and coastal resort cities, serving as a transportation corridor connecting Salt Lake City, Denver, Kansas City, St. Louis, Indianapolis, Columbus, Ohio, Pittsburgh, Baltimore, Wilmington, Delaware, and Philadelphia. Established in 1926, the route overlays older trails, canals, and turnpikes associated with westward expansion, commerce, and urban growth.

Route description

US 40 begins near Park City, Utah on the eastern approaches to the Wasatch Range, descending into the Great Salt Lake basin and joining corridors that serve Interstate 80 and Interstate 70. In Colorado the highway traverses the Rocky Mountains via mountain passes and connects with Denver International Airport approaches and the South Platte River valley. Across the High Plains, US 40 passes through Greeley, Colorado, Oakley, Kansas, and agricultural communities tied to the Missouri River watershed before reaching Kansas City, Missouri and joining riverfront approaches near Westport and Country Club Plaza. East of St. Louis, the route parallels sections of the Mississippi River and crosses into Illinois near East St. Louis with access to the Gateway Arch National Park area.

Continuing into the Midwest, US 40 serves Effingham, Illinois and links to Decatur, Illinois and Terre Haute, Indiana, crossing the Wabash River and entering Indianapolis where it uses urban arterials and bypasses into the Interstate Highway System network. Through Ohio, the highway passes near Vandalia, Ohio, Dayton, Springfield, Ohio, and Columbus, Ohio, connecting to historic canal towns and industrial suburbs. Entering the Appalachian region, US 40 ascends toward Cumberland, Maryland and skirts Frostburg, Maryland before descending to the Allegheny Plateau and following routes toward Pittsburgh, Pennsylvania and the Monongahela River valley.

In the Mid-Atlantic, US 40 parallels the National Road alignment through Hagerstown, Maryland, Frederick, Maryland, and Baltimore, where it becomes urban arterial streets and crosses the Patapsco River. East of Baltimore, the route serves Dover, Delaware corridor connections and proceeds through Wilmington before entering New Jersey, traversing suburban and Atlantic coastal plains to terminate at the oceanfront in Atlantic City.

History

The corridor of US 40 follows pieces of the National Road, authorized by the Congress of the United States in the early 19th century to link the Potomac and the Ohio River valleys. Early alignments incorporated the Cumberland Road and stages of the Lincoln Highway and Victory Highway systems. The 1926 designation of the U.S. Numbered Highway System assigned the US 40 number to this transcontinental corridor, integrating established turnpikes and state roads. During the Great Depression and the New Deal era, federal programs such as the Works Progress Administration and the Civilian Conservation Corps funded improvements and bridges along US 40, while wartime mobilization in the 1940s increased importance of sections near Oak Ridge, Tennessee and industrial centers.

Postwar development led to construction of Interstate 70 and Interstate 80, which paralleled or supplanted long rural stretches of US 40, leading to decommissioning, rerouting, or downgrading of segments into state highways and business routes. Urban renewal projects in cities like Baltimore and Denver altered alignments, while preservation movements in Cumberland and Zanesville, Ohio worked to conserve historic segments and milestones. Major floods, including events on the Mississippi River and Ohio River, prompted realignments and bridge replacements; notable dedications include memorials near Constitution Square and markers referencing Lewis and Clark era trails and George Washington survey routes.

Major intersections and termini

US 40 intersects and parallels multiple major routes: Interstate 80 in Utah and Nevada approaches, Interstate 70 across Colorado and the Midwest, Interstate 35 in Kansas City, Interstate 55 and Interstate 64 near St. Louis, Interstate 65 and Interstate 74 in Indiana, Interstate 71 and Interstate 270 (Ohio) in the Columbus, Ohio area, Interstate 76 and Interstate 79 near Pittsburgh, Interstate 95 in the Mid-Atlantic corridor, and Garden State Parkway and Atlantic City Expressway near its eastern terminus. Western termini link with mountain passes toward Salt Lake City and Park City, while the eastern terminus fronts the Atlantic Ocean at Atlantic City, adjacent to boardwalk and casino districts.

Special routes and alignments

Numerous business routes, alternate alignments, and bypasses exist: US 40 Business through downtown Columbus, Ohio, US 40 Alternate near Kansas City, Kansas, business loops in Cumberland, Maryland and Hagerstown, Maryland, and truck bypasses around St. Louis and Indianapolis. Historic alignments preserve segments of the National Road as scenic byways and state historic routes, with preserved brick pavements in towns like Zanesville and surviving mileposts and toll houses near Brownsville, Pennsylvania. Ferry connections historically linked discontiguous segments across large rivers before bridge construction tied the route into continuous alignments near Hawkins Ferry and Chesapeake Bay approaches.

Notable landmarks and cultural significance

US 40 passes or provides access to a wide array of landmarks: Great Salt Lake, Garden of the Gods, Rocky Mountain National Park approaches, National World War I Museum and Memorial vicinity in Kansas City, Gateway Arch, Lincoln Home National Historic Site proximities, Eiteljorg Museum approaches in Indianapolis, National Road National Historic Trail segments, C&O Canal National Historical Park near Cumberland, Fort Necessity National Battlefield environs, Gettysburg National Military Park connections via spur roads, and maritime attractions in Atlantic City including the Absecon Lighthouse. Cultural institutions along the route include the Denver Art Museum, St. Louis Art Museum, Columbus Museum of Art, Carnegie Museum of Natural History in Pittsburgh, Baltimore Museum of Art, and performing arts venues tied to Broadway touring circuits in several cities. The corridor is associated with literature and music that reference cross-country travel, including works tied to Route 66 era narratives and the folk traditions of Appalachian and Midwestern communities.

Future developments and improvements

Planned improvements include pavement rehabilitation projects funded by state departments of transportation such as the Utah Department of Transportation, Colorado Department of Transportation, Missouri Department of Transportation, Indiana Department of Transportation, Ohio Department of Transportation, Maryland Department of Transportation, and New Jersey Department of Transportation. Proposals involve interchange upgrades with Interstate 70 and Interstate 95, multimodal enhancements near Baltimore-Washington International Airport, bridge replacements over tributaries of the Ohio River and Mississippi River, and streetscape revitalization projects in historic downtowns like Hagerstown and Cumberland. Transportation planning collaboratives including the Metropolitan Transportation Authority (New York)-area partners, regional planning commissions, and federal grant programs aim to balance preservation of National Road heritage with modernization to support freight movements connected to ports such as Port of Baltimore and Port of Philadelphia.

Category:United States Numbered Highways