Route 123 (Chain Bridge Road) Interchange

Major reconstruction of the Route 123 (Chain Bridge Road) Interchange is a part of the Transform 66 Outside the Beltway Project. The new interchange design:

Provides access to and from the express lanes from I-66 East and West
Improves safety at the interchange
Connects the City of Fairfax and the planned George Snyder Trail with the new shared-use path and neighborhoods in Oakton with a grade-separated trail through the Route 123 Interchange

Get a closer look with the Transform 66 Interactive Map.

Express Lanes Access at Route 123

A ramp from both northbound and southbound Route 123 to the eastbound 66 Express Lanes.
A ramp from both northbound and southbound Route 123 to the westbound 66 Express Lanes.
Ramps from both directions of the 66 Express Lanes to Route 123 North and South.

Drivers will have improved connections from Route 123 North and South to the I-66 East and West general-purpose lanes.

66 Express Lanes Access at VA-123

Construction Update (Updated September 11, 2023)

Construction Progress:

Route 123 North and South bridges are open and in use and the travel lanes in both directions approaching I-66 have shifted into their permanent alignment
Box culverts have been installed for shared-use path through the interchange
All I-66 East and West travel lanes have shifted to new pavement on the right side (outer portion) of the roadway
New ramps have opened for Route 123 North to I-66 West (opened November 2021), Route 123 South to I-66 East (opened March 2022), and Route 123 South to I-66 West (opened April 2022)

Upcoming Construction Activities:

Completion of shared-use path along I-66 (66 Parallel Trail) and into City of Fairfax along Route 123 (connection to George Snyder Trail)
Planting trees, shrubs, and grass at multiple locations in the interchange
Construction of new intersection between I-66 and Eaton Place

Aerial view of the Route 123 area

Aerial view of the Route 123 area. (April 2023)

Timeline

Anticipated Schedule	Dates
Clearing activities begin	Spring 2018
Traffic pattern shifts begin	April 2019
Ramp and bridge work begin	Summer 2019
Demolition of ramp from I-66 West to Route 123 South	January-February 2020
Traffic shifts to new Route 123 bridge span	December 30, 2020
Demolition of old Route 123 bridge span	January-February 2021
Construction of second Route 123 bridge span begins	Winter 2021
Express Lanes opened	November 2022
Shared-use path through interchange opens	September 2023
New intersection opens between I-66 and Eaton Place	September 2023