Virginia State Route 606 (Fairfax and Loudoun Counties)

In Reston, SR 606 is called Baron Cameron Avenue. Baron Cameron Avenue starts at an intersection with SR 7, Leesburg Pike. For a short distance (0.18 mi.) SR 606 is concurrent with SR 674. Baron Cameron Avenue then travels westward through the northern part of Reston to the Herndon border.

The Town of Herndon is responsible for the maintenance of its streets,[4] although the Virginia Department of Transportation(VDOT) helps towns and cities financially, and has designated these roads with state route numbers.[5]

Although SR 606 technically ends at the Herndon border, roads within Herndon are signed as SR 606, and they provide a direct connector to SR 606 in Loudoun County, so they are included here. When SR 606 enters the town the route changes to Elden Street, the main commercial road of Herndon. When Elden Street intersects with SR 228, Elden Street becomes SR 228. (signed) SR 606 is concurrent with SR 228 / Elden Street to Sterling Road, where the route continues west toward Loudoun County.

In Loudoun County SR 606 continues the path of Sterling Road as a four lane divided highway called Old Ox Road. It heads west until it crosses over SR 28, Sully Road at an interchange. It continues toward the Dulles Greenway (SR 267) as it passes some warehouses on the south side. The intersection with the Dulles Greenway is the planned location for the Route 606 station of the proposed Phase 2 of the Silver Line of the Washington Metro.

View east along SR 606 in Dulles

After the interchange with the Dulles Greenway, SR 606 turns to the southwest and goes around the back of Dulles Airport. It passes some single-family houses to the west, and Dulles Airport and some low rise office buildings to the east.

There is a sign as Arcola is approached that shows that the name of the roadway is now the Loudoun County Parkway. Shortly before the intersection with SR 621 (Evergreen Mill Road), the road expands back to a four lane divided highway. It continues as such past the intersection with US 50, passes through a portion of South Riding, and terminates at SR 620 (Braddock Road).

VDOT has plans to widen Elden St. between Van Buren Street and the Fairfax County Parkway (SR 286). However, due to budget cutbacks, this project has been put on hold.[6]

Before construction on the Loudoun County Parkway started, SR 606 ended at the intersection with US 50. As of March 2010, SR 606 has been extended from US 50 to SR 620 (Braddock Road). The portion between SR 620 and Arcola has been designated part of the Loudoun County Parkway, and is a four-lane divided highway.