I-70

I-70
Name	Interstate 70
Route number	70
Length mi	2151.43
Established	1956
Terminus a	Near Cove Fort, Utah
Terminus b	Baltimore, Maryland
States	Utah; Colorado; Kansas; Missouri; Illinois; Indiana; Ohio; West Virginia; Pennsylvania; Maryland

I-70 is a major east–west United States Interstate Highway corridor traversing the central and eastern United States. Beginning near Cove Fort, Utah and terminating in Baltimore, Maryland, the route links Rocky Mountain passes, Great Plains expanses, Midwest industrial centers, and Mid-Atlantic ports. It serves metropolitan areas including Denver, Kansas City, St. Louis, Columbus, Pittsburgh, and Baltimore, and intersects national corridors such as Interstate 15, Interstate 25, Interstate 35, Interstate 55, and Interstate 95.

Route description

The western segment crosses the Wasatch Plateau and connects to the San Rafael Swell before entering Colorado near Grand Junction and the Colorado National Monument. In Colorado, the highway ascends the Gore Range and traverses the Eisenhower Tunnel approach corridors, approaching the Denver region where it intersects I-25 and the E-470 beltway. East of Aurora the route crosses the Plains, passing through Limon toward Kansas City via Topeka and Salina. In Missouri, the highway skirts Warrensburg and meets the Missouri River at Kansas City where it converges with I-635 and I-470. Continuing, it proceeds to Columbia and Jefferson City before reaching the St. Louis and crossing the Mississippi River onto the Illinois River corridor near East St. Louis. Through Illinois, I-70 links to Illinois Route 3, I-64, and passes south of Effingham toward the Indiana boundary. In Indiana, it serves Vincennes and joins I-465 around Indianapolis, then continues east to Richmond and crosses into Ohio near Dayton and Columbus. The Ohio segment connects with I-71 and I-77 near Mansfield before reaching the Pennsylvania border. In Pennsylvania, the highway traverses the Allegheny Plateau toward Pittsburgh, where it intersects I-79 and I-376, then crosses the Fort McHenry Tunnel approach corridors into Baltimore and terminates near Inner Harbor.

History

Planning roots trace to the Federal-Aid Highway Act of 1956 and earlier transcontinental routes such as U.S. Route 40 and U.S. Route 66. Early construction milestones included completion of mountain grade segments in Colorado Rockies and urban bypasses in St. Louis and Indianapolis. Notable engineering projects included bore construction near the Eisenhower Tunnel and river crossings at Mississippi River and Missouri River. Expansion and modernization efforts paralleled federal and state funding initiatives like Interstate Highway System appropriations and later Infrastructure Investment and Jobs Act allocations. Major disruptions affected the corridor during events such as severe winter storms and floods that closed segments near Fort Collins and Richmond, prompting resilience projects linked to agencies including Federal Highway Administration and state departments of transportation like the Colorado Department of Transportation and Maryland Department of Transportation. Historic alignments preserved portions of National Register of Historic Places corridors and intersect with cultural sites such as the Amish Country near Lancaster and the Gettysburg National Military Park region.

Major intersections

Key interchanges include junctions with I-15 near Cove Fort, I-25 in Denver, I-35 in Kansas City, I-55 in St. Louis, I-64 in St. Louis/Louisville corridors, I-75 proximity at Dayton and Cincinnati approaches, I-65 near Indianapolis, I-71 in Columbus, I-79 in Pittsburgh, and terminal adjacency to I-95 and Baltimore Harbor Tunnel approaches. Other significant connectors include I-470, I-270, I-465, I-275, I-670, and toll facility interchanges with Pennsylvania Turnpike and Kansas Turnpike Authority sections.

Auxiliary routes

Auxiliary freeways associated with the corridor include numbered spurs and loops such as I-170 in St. Louis County, I-270 beltway near St. Louis, I-470 near Kansas City, I-670 in Columbus, I-470 in Steubenville/Wheeling regions, and I-170 proposals related to Baltimore. State routes and business loops include former alignments of U.S. Route 40, U.S. Route 24, and U.S. Route 6 that serve local communities from Grand Junction to Baltimore Inner Harbor. Metropolitan connectors like Spaghetti Junction-style interchanges in Kansas City and Columbus align with regional arterials including U.S. Route 36 and U.S. Route 50.

Services and amenities along the route

Corridor amenities serve freight and passenger needs with truck plazas near Limon, travel plazas in Kansas, rest areas in Missouri and Ohio, and tourist information centers at state welcome plazas like Wyoming? (state-specific). Commercial nodes include logistics hubs near Denver International Airport, rail interchanges at Kansas City Southern, intermodal yards in Columbus, and port access to Port of Baltimore. Hospitality and cultural stops range from historic motels along U.S. Route 40 to museums such as the National Museum of the United States Air Force near Dayton and the John F. Kennedy Center for the Performing Arts proximity via connecting routes. Emergency services coordination involves state police units like Colorado State Patrol, Kansas Highway Patrol, Missouri State Highway Patrol, and Maryland State Police.

Future developments and improvements

Planned projects include capacity expansions, interchange reconstructions, and resilience upgrades funded through programs like the Infrastructure Investment and Jobs Act and state bond measures. Major corridor studies consider congestion relief in the Denver metro via managed lanes and in Columbus and Pittsburgh through interchange modernization tied to Federal Highway Administration grants. Environmental and multimodal initiatives intersect with projects such as freight rail diversion proposals involving BNSF Railway and Union Pacific Railroad corridors, and transit-oriented development near Baltimore and Kansas City interchanges. Long-term proposals evaluate mountain pass avalanche mitigation near Colorado Rockies and bridge replacements over the Mississippi River in the St. Louis area, coordinated with agencies like the U.S. Army Corps of Engineers and state departments of transportation.

Category:Interstate Highways