Interstate 66 in Virginia

By | October 14, 2022


Get started Middletown
End Washington
Length 76 mi
Length 123 km
0 → Roanoke / Hagerstown6 Winchester

13 Linden

18 Markham

23 Delaplane

27 Marshall

28 Warrenton

31 Old Tavern Road

40 Leesburg

43 Gainesville

44 Prince William Parkway

47 Manassas

52 Centerville

53 Dulles Airport

55 Springfield

57 Winchester

60 Fairfax

62 Vienna

64 → Washington Beltway

66 Falls Church


68 Westmoreland Street

69 Lee Highway

71 Glebe Road

72 Lee Highway

73 Rosslyn

75 Pentagon

George Washington Mem. parkway

Independence Avenue

Constitution Avenue

E Street

Whitehurst Freeway

Rock Creek Parkway

Pennsylvania Avenue

Canal Road

M Street

Interstate 66 or I -66 is an Interstate Highway in the United States. The highway runs in northern Virginia from Interstate 81 at Middletown to Washington DC. The route is 124 kilometers long, of which 3 kilometers is in the District of Columbia.

  • WATCHTUTORIALS.ORG: Features why Virginia has the nickname as Old Dominion and its economy, history and geography.

Travel directions

I-66 on the western portion of the route.

I-66 in the suburbs of Fairfax County.

The highway begins at Interstate 81, which runs from Roanoke to Hagerstown, near Middletown, in northern Virginia. There are 2×2 lanes available. After a few kilometers you pass the regional town of Front Royal, located on the Shenandoah National Park. You then cross the Manassas Gap, a low pass of 270 meters high. Further towards Washington the highway gets busier and busier. The first suburb is Gainesville, 55 kilometers from Washington. Like many suburbs in the northeastern United States, Washington’s is relatively sparsely built and located in dense forests. A somewhat larger suburb is Centerville. From here, 2×4 lanes are available. At Fairfax you cross US 50, the main road from Winchester to Washington. Closer to Washington, the road narrows to 2×3 lanes. At Merrifield one crosses Interstate 495Washington Beltway. From here the road even narrows to 2×2 lanes, and huge traffic jams can occur. Light rail stations are located in the median strip of I-66. A few miles away, SR-267, Dulles Airport Access Road, ends on I-66.

One now passes through more densely built-up areas, although the building density is not yet as high as cities on the west coast. You then arrive in Arlington, with 203,000 inhabitants a city in itself. Arlington itself has quite a lot of high-rise buildings, and also functions as an independent city. Here too, the I-66 has only 2×2 lanes, in the middle of a multimillion-dollar area. On the bank of the Potomac River, one crosses the Jefferson Davis Highway, and the George Washington Memorial Parkway, two highways leading to the Pentagon, which is a little further south. The Theodore Roosevelt Memorial Bridge crosses the Potomac River, which is about 600 meters wide here. This bridge is special because it has a movable central barrier, so that more lanes can be made available in the rush hour direction. Several monuments are visible from the bridge, such as the Lincoln Memorial and the Washington Monument. In the District of Columbia, the highway turns north, crossing some well-known streets such as Constitution Avenue, E Street, and Virginia Avenue, to end at US 29, the Whitehurst Freeway, which becomes K Street.

  • Provides state overview of Virginia and its alternative name as The Old Dominion State


The Theodore Roosevelt Bridge over the Potomac was inaugurated on June 23, 1964. The US 50 ran over it at the time. Interstate 66 was built later. I-66 was one of the last major routes of Interstate Highways to be significantly completed until the late 1970s. The western Virginia portion was opened in two phases in 1971 and 1979, but the Washington DC suburban portion was not completed until 1982 after many lawsuits and delays. I-66 was originally planned to run east through Washington DC, but this section has been scrapped, as has I-95 through DC

Opening history

From Unpleasant Length Opening
exit 43 Exit 52 14 km 16-12-1961
Exit 23 Exit 27 7 km 18-05-1962
Exit 75 Exit 76 2 km 23-06-1964
Exit 52 Exit 64 19 km 18-11-1964
exit 0 exit 6 10 km 12-10-1971
Exit 27 exit 28 2 km 03-08-1979
exit 6 Exit 23 27 km 30-08-1979
exit 28 Exit 40 19 km 20-12-1979
Exit 40 exit 43 5 km 19-12-1980
Exit 64 Exit 75 19 km 22-12-1982


I-66 has been gradually widened west to 2×4 lanes. In or before the 1980s, I-66 between Fairfax and I-495 was widened to 2×4 lanes, followed by the section to Manassas in the latter half of the 1990s. In 2006, the section between Gainesville and Manassas was widened to 2×4 lanes and between 2014 and 2016, 5 miles of I-66 between Haymarket and Gainesville was widened from 2×2 to 2×4 lanes. The extra lanes opened to traffic on August 23, 2016.

Within I-495, I-66 was constructed in 1982 with only 2×2 lanes and high tolls are required to ensure free-flow traffic. On December 7, 2017, a $86 million contract was awarded to build a 6-kilometer third lane between VA-267 (Dulles Connector Road) and Fairfax Drive. The works were carried out between 2018 and 2020.

HOV / toll

I-66 in Arlington, originally HOV-only.

I-66 was originally reserved entirely for HOV vehicles during rush hour on the section between I-495 and US 29 in Rosslyn, on the west side of Washington. This was the only highway in the United States that vehicles with a single occupant were not allowed to use during rush hour.

On February 10, 2016, an agreement was reached on the approach to I-66 within the Beltway (I-495). In 2017, the ‘HOV-only’ function was scrapped and it became a toll road during rush hours, in the morning towards Washington and in the afternoon towards the suburbs. I-66 is toll-free outside rush hours and on weekends. The amount of the toll depends on the current traffic flow, the goal is to keep I-66 free-flow at all times. Tolls began on December 4, 2017. In the early days, the demand-driven dynamic tolls spiraled out of control, peaking at $34.50 – $40.00 for the 13-kilometer stretch.



I-66 will be provided with express lanes in the western suburbs of Washington, on a 42-kilometer stretch between I-495 and US 29 in Gainesville. This section used to have between 2×2 and 2×4 lanes. As part of the project, 2×3 lanes will be constructed as toll-free general purpose lanes throughout, plus two toll lanes with a variable toll rate per direction. This project is called ‘Transform 66’. On November 3, 2016, a 50-year concession was awarded to the Express Mobility Partners consortium to construct the toll lanes. The contract value is over $3 billion. Work officially started on November 21, 2017. The project should be completed by December 2022.

Other states

There were plans to turn Interstate 66 into a transcontinental route from California to Washington, DC. The route through California and Nevada has been canceled due to lack of traffic. Also, the route west of Wichita, Kansas is not a serious proposal. Due to a lack of money, the chance that the I-66 will be realized in the foreseeable future is very small.


In Kansas, I-66 would run from Wichita to Joplin, Missouri. This route is currently served by US 400.


In Missouri, I-66 should form an east-west route through the south of the state. There are roughly two options, a somewhat northerly route to Cape Girardeau, and a somewhat more southerly route to Sikeston. Both routes have been the subject of a study.


The northern route in Missouri would run I-66 through southern Illinois. The state of Illinois never had much interest in an I-66 given the low population density of southern Illinois and the already adequate road network for regional traffic. It is planned to make some upgrades under the name ‘Shawnee Parkway’, but this will not be an Interstate Highway.


In Kentucky, I-66 is the most concrete, partly because existing highways can be used here, such as the Western Kentucky Parkway, the Natcher Parkway and the Cumberland Parkway. However, the construction of a few links is necessary in central southern Kentucky. Also needs an upgrade of the Hal Rogers Parkway which is a super two. No route has yet been established in eastern Kentucky, construction costs are high because of the mountainous terrain.

West Virginia

In West Virginia, I-66 should run as far as planned Interstate 73 / Interstate 74, not far from the Kentucky border. The rest of the route through West Virginia is not planned. However, some Appalachian Development Highway System routes are planned, prominently the Corridor H. However, this is not planned as a full-fledged freeway.

Traffic intensities

Traffic intensities are already quite high in rural areas with 40,000 vehicles per day. The busiest point is at Fairfax with 188,000 vehicles per day. I-66 is heavily congested in the Washington metropolitan area.

Lane Configuration

From Unpleasant Lanes Comments
exit 0 Exit 40 2×2
Exit 40 exit 57 2×4 Haymarket – Fairfax
exit 57 Exit 64 2×3 Fairfax
Exit 64 Exit 67 2×2 Arlington
Exit 67 Exit 72 2×3 Arlington
Exit 72 Exit 75 2×2 Arlington
Exit 75 K street 2×3 Washington

Interstate 66 in Virginia