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Interstate 66

Total length: 76 miles (122 km)
Western terminus: Middletown, VA, at JCT I-81
Eastern terminus: Washington, DC, at JCT U.S. 29

States traversed & length in each:

• Virginia — 75 miles (120 km)
• District of Columbia — 1 mile (2 km)

Major cities along route:

• Arlington, VA
• Washington, DC

Junctions with non-related Interstates:

• Interstate 81: Western terminus in Middletown, VA
• Interstate 495: Exit 64 in Dunn Loring, VA

Related loops and spurs:

NONE

Length I’ve traveled: From western terminus to VA Exit 64 (I-495)

Time zones:
Eastern — Entire length

Counties traversed:
Virginia — Warren, Fauquier, Prince William, Fairfax Co., CITY OF FAIRFAX, (re-enters Fairfax Co.), (re-enters CITY OF FAIRFAX), (re-enters Fairfax Co.), CITY OF ARLINGTON

District of Columbia — CONTAINS NO COUNTIES

NOTE: Independent cities in Virginia are in ALL CAPS and are noted by “CITY OF ____.”

A quick hypertext drive: Interstate 66 is a short connecting route across the booming Northern Virginia region, connecting our national capital of Washington with points to the southwest that can be accessed via Interstate 81. The first several miles from the western terminus are fairly flat, running in the Shenandoah River valley, but they belie the mountainous nature of the surrounding area; in fact, the famous Skyline Drive, a scenic National Park Service highway, is accessed via U.S. Route 340 at Exit 6. As I-66 proceeds east, it becomes significantly more hilly, although not tremendously so, across northern Fauquier County.

Just west of Manassas, around milepost 42, I-66 very quickly widens from four lanes to eight and flattens out considerably. It is an otherwise unremarkable suburban freeway from there to Centreville, where the right-hand shoulders in both directions have been cannibalized for part-time traffic use (open eastbound during the morning rush hour, and westbound in the evening; reserved as a breakdown lane at all other times). This arrangement persists through the Fairfax area all the way to I-495/Capital Beltway, where I-66 immediately narrows back down to four lanes.

The reason for I-66’s quick narrowing at I-495 is an early-1970s compromise with local residents without which I-66 into Washington would never have been completed. Under the terms of the settlement, only a four-lane freeway with draconian traffic restrictions could be built. Inbound traffic in the morning, and outbound traffic in the evening, is restricted to HOV-2 (at least two-person carpool) vehicles, and large trucks are prohibited on I-66 inside the Beltway at all times.

In the Arlington neighborhood of Rosslyn, I-66 passes by the Marine Corps War Memorial, a bronze statue depicting the world-famous image of the servicemen who raised the American flag on Iwo Jima during World War II. Immediately after passing by that, it crosses the Theodore Roosevelt Bridge into Washington, and then curves north past the Watergate Hotel, terminating at U.S. Route 29 just blocks northwest of the White House.

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