About Unbuilt Interstate 266 | Web Links | Sources
Interstate 266 would have branched off Interstate 66 at a location between north of Spout Run and Rosslyn. Once across the Potomac River Interstate 266 would interchange with the then proposed Potomac Freeway. The Potomac Freeway was also known as the Palisades Parkway/Expressway in some planning studies. On the DC Shoreline and after the interchange with the Potomac Freeway, Interstate 266 would have turned east towards Georgetown and connected with the Whitehurst Freeway. The Whitehurst Freeway would have been reconstructed and widened to accommodate the increased traffic that would have resulted from Interstate 266. Interstate 266 would have ended at Interstate 66 near the Watergate complex. Interstates 66 and 266 combined would have provided 12 lanes of capacity into and out of the District.
Planning for Interstate 266 started in the mid 1960's. A September 1964 location study done by Howard, Needles, Tammen and Bergendoff Consulting Engineers proposed three general plans as the map below details.
The map above shows the proposed Interstate 66 and 266 cooridors from the Spout Run area east and north to the Potomac River. The road running generally east/west along the Interstate 66 proposed route is US 29 Lee Highway. The George Washington Memorial Parkway runs along the Virginia shoreline of the Potomac River. On the District side of the Potomac River, the proposed route of the Potomac Freeway generally follows Canal Road and the Whitehurst Freeway.
The general details of each of the plans are below. Click on each of the "Plan" hyperlinks to get detailed maps and artists renderings of each of the plans.
By November 1973, the "I-66 Corridor Transportation Alternatives Study: Draft Environmental/Section 4(f) Statement" showed a slightly modified Plan II (from the September 1964 study) as the alternative that was to receive additional study. It should noted here that Interstate 266 was being studied as a part of the entire Interstate 66 cooridor by now instead of a seperate road on its own. This makes sense because without Interstate 66 built, there is no purpose or need for Interstate 266.
Below are two maps from "I-66 Corridor Transportation Alternatives Study: Draft Environmental/Section 4(f) Statement" showing details of the route that was being studied. Note that the November 1973 study was slightly different than the September 1964 study in that Spout Run Parkway goes under Interstate 66 as opposed to over and there is no upriver access to Canal Road on the District Side of the Potomac River. Also, there is no tunnel for Interstate 266 in the Spout Run Valley and the interstate efffectively replaces Spout Run Parkway instead of being seperate from it as is described in the September 1964 study. Lastly, the Potomac Freeway is no longer shown on the District side of the Potomac River.
As Virginia and the District advanced their collective freeway plans, community opposition increased. Interstate 266 and the Three Sisters Bridge were the subject of lawsuits and protests. Construction on Interstate 266 was started only to be stopped by a court injuction in 1970. The injunction was confirmed on appeal in 1972. Only the footings for the Three Sisters Bridge on the District side of the Potomac River were built. Utlimately, Interstate 266 was cancelled in the mid to late 1970's. Funds from Interstate 266 were spent on other transportation projects. Interstate 66 was built, but with a significantly scaled down plan. Scott Kozel has an excellent history of the consturction of Interstate 66 inside the Capital Beltway at his website.
Please send any updates, comments and corrections to Michael Hale.
Last Update: 1/28/08