Interstate 66 (abbreviated I-66) is an interstate highway in the eastern United States. As indicated by its even route number, it runs in an east-west direction. Its western terminus is at Middletown, Virginia at an intersection with Interstate 81 (Map); its eastern terminus is at Washington, D.C. at an intersection with United States Highway 29. (Map)

Length

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Miles	km	state
75	121	Virginia
2	3	District of Columbia
77	124	Total

Major cities

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Bolded cities are officially-designated control cities for signs.

• Strasburg, Virginia
• Front Royal, Virginia
• Washington, D.C.

Intersections with other interstates

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• Interstate 81 in Middletown, Virginia
• Interstate 495, the Capital Beltway at Falls Church, Virginia

Auxiliary routes

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No auxiliary routes were constructed. Interstate 266 was planned in northern Virginia and Washington, D.C. It was cancelled in 1972 due to community opposition and environmental concerns.

Notes

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• Because I-66 is the only major highway running west from Washington, D.C., into Northern Virginia, traffic on the road is often extremely heavy. For decades, there has been talk of widening I-66 from 2 to 3 lanes each way inside the Capital Beltway (through Arlington, Virginia), although many Arlington residents are adamantly opposed to this plan. Studies are being conducted by VDOT on the prospect of implementing this one-lane extension on westbound I-66 within the Beltway (thus alleviating congestion for people commuting away from DC).
• Because of that heavy traffic, I-66 has HOV lanes.
  • Between Route 234 in Manassas, Virginia and the Beltway, the left lane on eastbound I-66 is reserved for HOV-2 during morning rush hour, and the left lane on westbound I-66 is reserved for HOV-2 during evening rush hour. Also during those rush hours, between Route 50 and the Beltway, the right-hand shoulder is available for use as a travel lane.
  • Within the Beltway (between the Beltway and the Theodore Roosevelt Bridge), the entire eastbound (inbound) roadway is reserved for HOV-2 and Dulles Airport traffic during morning rush hour, and the entire westbound (outbound) roadway is reserved for HOV-2 and Dulles Airport traffic during evening rush hour. This is readily and easily enforced, since no single-passenger vehicles are allowed to come onto the highway at all within the beltway in the direction of rush-hour traffic. These restrictions may result more in a displacement of rush-hour than in an alleviation; I-66 is observed as relatively clear where and when they are in place, and congested for some time before and after.
    • This is the only 2 digit Interstate to enter the District of Columbia (other than the 100 yards (100 m) or so that I-95 passes through DC on the Woodrow Wilson Bridge). I-66 was planned to intersect I-95, before I-95 was rerouted to the east side of the Capital Beltway.
    • In 2005, as part of the reconstruction of the plaza in front of the John F. Kennedy Center for the Performing Arts, an entrance was opened from 25th Street, N.W., to westbound I-66. However, at least one sign in the vicinity misidentified the route as the unrelated (and no longer existent) U.S. Highway 66.
    • Construction is currently underway for the widening of I-66 on both East and Westbound routes between Route 234 in Manassas and the westernmost intersection with U.S. Route 29 in Gainesville

    Historical controversy

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    As with many urban interstate highway projects, I-66 has encountered opposition from local citizen groups. Most notably for I-66 was the construction through Arlington, Virginia, proposed in 1956. After the Virginia Department of Transportation (VDOT) (then known as the Virginia Department of Highways) acquired two sections of the former route of the Washington and Old Dominion Railroad to provide a right-of-way through Arlington for the new highway, the Arlington Coalition on Transportation (ACT) filed a lawsuit in Federal District Court in 1971 opposing the Arlington portion of the project. The group objected to that urban segment due to concerns over air quality, noise and community cohesion changes. In 1972 the U.S. Fourth Circuit Court of Appeals ruled in favor of ACT, technically blocking any construction. The U.S. Supreme Court upheld the ruling in favor of ACT later in 1972Jay Mathews, High Court Backs Delay Of Rte. 66, The Washington Post, Times Herald, Washington, D.C., Nov 7, 1972. The impasse was eventually broken when the parties agreed on experts to conduct air quality and noise studies for VDOT; the firm of ESL Inc., the expert hired originally by ACT, was agreed upon to be hired by VDOT. Then, U.S. Secretary of Transportation Coleman personally intervened in 1976 with negotiations to reach a compromise of a reduced highway width including a transit element.Hogan, C. M. and Harry Seidman, Air Quality and Acoustics Analysis of Proposed I-66 through Arlington, Virginia, ESL Inc. Technical Document T1026, Sunnyvale, Calif. (1971)

    Less controversial was the portion of the highway's route immediately west of Arlington. There, VDOT decided to curve the highway to bypass the City of Falls Church, increasing the interstate's length while sparing the city from the road's immediate environmental impacts.

    Extension projects

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    The U.S. Department of Transportation has had plans to extend I-66 westward across the country to California. However, Interstate 66 west of Wichita, Kansas has been canceled. This was due to several reasons, among them: lack of interest in the states west of Kansas, insufficient traffic for an interstate in the area (in fact, in some places a highway didn't exist at all), and the route was to go through Death Valley National Park (to which the National Park Service was strongly opposed). The main reason for that specific number was to capitalize off U.S. Highway 66 and was started by businessmen in Wichita.

    Former Governor Paul Patton has written I-66 into law in Kentucky, with the routing being confirmed along the Hal Rogers Parkway (formerly Daniel Boone Parkway) and the Louie B. Nunn Cumberland Parkway. Preliminary construction has started on a segment in Pulaski County. There would be a long section with a southwest-northeast trajectory required to connect with the existing I-66; many believe a lower number (there are no east-west Interstates numbered in the 50s, and the proposed highway is south of Interstate 64) would make more sense for the Kentucky extension.

    Missouri has had several proposals to bring I-66 through the state over the years. Currently the two main locations for consideration are bringing I-66 from Kentucky through Illinois to Cape Girardeau (which would require going through Shawnee National Forest), or bringing the route through close to the current bridges by Wyatt to Sikeston where it could multiplex onto the current U.S. Route 60 westward. Illinois has only recently gained interest in bringing I-66 through their state. If Cape Girardeau and Illinois cannot lure Congress to modify the route through there, Sikeston may eventually be the convergence point of three major Interstates, I-55 to St. Louis and Memphis, I-57 to Chicago, and the new I-66 to Kentucky and Washington, D.C. in addition to the considerable pieces of the U.S. Highway System already present there.

    Exit list

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    Virginia

    Interstate 81US 522.svgUS 340 / US 522VA Route 55 Shield.PNGUS 17 North / Route 55 West US 17.svgRoute 55 East / Route 647 / US 17 Business US 17 South / US 17 Business US 15US 29, GainesvilleRoute 234 South / Prince William Parkway Route 234 North / Business Route 234 / Sudley Road US 29, CentrevilleRoute 28 / Sully Road Route 7100 / Fairfax County ParkwayUS 50, Fair OaksRoute 123Interstate 495 / Capital Beltway
    (eastbound right exits in cloverleaf pattern plus left exit (HOV only during rush hour)
    westbound exit to I-495 South only) Route 7 / Leesburg PikeRoute 267 to Dulles Toll Road (westbound only) US 29 / Route 237 / Lee Highway / Washington Boulevard (eastbound)
    Sycamore Street (westbound) US 29 / Lee Highway / Spout Run Parkway (eastbound only) US 29 / Lee Highway / Key Bridge

    County	Municipality	Exit	Road(s) Intersected
    Frederick - Warren Boundary		1
    Warren	Front Royal	6
    		13	Route 79 to Route 55
    Fauquier		18	Route 688
    		23
    	Marshall	27
    	Marshall	28
    	The Plains	31	Route 245 / Old Tavern Road
    Prince William	Haymarket	40
    		43
    		44
    		47
    Fairfax		52
    		53
    		55
    		57
    Fairfax - Fairfax (City) Boundary	Fairfax (City)	60
    Fairfax	Vienna	62	Route 243 / Nutley Street
    		64
    		66
    		67
    Arlington		68	Westmoreland Street (eastbound only)
    		69
    		71	Route 120 / Glebe Road (eastbound and westbound) Fairfax Drive (Route 237) (eastbound only)
    		72
    		73
    		75	Route 110 South (eastbound only)

    District of Columbia

    US 50 West / Arlington Boulevard / George Washington Memorial Parkway US 50 East / Constitution Avenue / Downtown US 29 South / Whitehurst Freeway / Canal Road

    Mile	Destinations	Notes
    	westbound exit and eastbound entrance; US 50 joins eastbound and leaves westbound
    	Independence Avenue
    	eastbound exit and westbound entrance; US 50 joins westbound and leaves eastbound
    	E Street Expressway
    	Rock Creek Parkway	eastbound exit and westbound entrance
    	Pennsylvania Avenue	eastbound exit and westbound entrance
    	eastbound exit and westbound entrance

    References

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    External links

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    • HOV schedule in Northern Virginia, from Virginia Dept. of Transportation
    • Information on origin and future plans of I-66
    • Kentucky's Official Site for the Proposed Interstate 66
    • kick66.org website in opposition to the I-66 project in Kentucky

    Interstate Highway System | Interstate Highways in the District of Columbia | Interstate Highways in Virginia