Editing Interstate 66 (section)

=== Washington, D.C. ===
In [[Washington, D.C.]], the route quickly turns north, separating from US&nbsp;50. The highway interchanges with the E Street Expressway spur before passing beneath [[Virginia Avenue|Virginia]] and [[New Hampshire Avenue|New Hampshire Avenues]] in a short tunnel, also running on the east side of the [[Watergate complex]]. After an indirect interchange with the [[Rock Creek and Potomac Parkway]] (via 27th Street), the highway terminates at a pair of ramps leading to the Whitehurst Freeway (US&nbsp;29) and L Street. The portion of Interstate 66 within Washington, DC, is known as the Potomac River Freeway.

==== E Street Expressway ====
{{Infobox road small
|state=DC
|name=E Street Expressway
|location=[[Washington, D.C.]]
|length_mi=0.3
|length_ref=<ref name=estreet-googlemaps>{{google maps |url=https://www.google.com/maps/dir/38.8958094,-77.0512044/38.8954356,-77.0449238/@38.8958443,-77.0491556,18z/am=t/data=!3m1!4b1!4m2!4m1!3e0 |title=E Street Expressway |access-date=January 31, 2020}}</ref>
|formed=
|deleted=
|historic=
|yr_ref=
}}
[[File:2019-09-16 14 49 20 View east along the E Street Expressway from the overpass for 23rd Street Northwest in Washington, D.C..jpg|thumb|The E Street Expressway just east of I-66]]
The '''E Street Expressway''' is a 480 meter long spur of I-66 that begins at an interchange with the Interstate just north of the Roosevelt Bridge. It proceeds east, has an interchange with Virginia Avenue Northwest, and terminates at 20th Street Northwest. From there, traffic continues along E Street Northwest to 17th Street Northwest near the [[White House]], the [[Old Executive Office Building]], [[George Washington University]], and the [[Corcoran Gallery of Art]]. Westbound traffic from 17th Street takes a one-block segment of [[New York Avenue (Washington, D.C.)|New York Avenue]] to the expressway entrance at 20th and E streets northwest. The expressway and the connecting portions of E Street and New York Avenue are part of the [[National Highway System (United States)|National Highway System]].

In 1963, the construction of the E Street Expressway caused the demolition of multiple buildings of the [[Old Naval Observatory]].<ref name=":0">{{Cite web|last1=Harden|first1=Victoria A.|last2=Lyons|first2=Michele|date=2018-02-27|title=NIH's Early Homes|url=https://irp.nih.gov/catalyst/v26i2/nih-s-early-homes|access-date=2020-09-28|website=The NIH Catalyst|language=en}}</ref>

;Exit list
The entire route is in the [[Foggy Bottom]] neighborhood of [[Washington, D.C.]] All exits are unnumbered.{{jcttop|nocty=yes|location=none|hatnote=off|length_ref=<ref name=estreet-googlemaps/>}}
{{DCint
|mile=0.00
|road={{jct|state=DC|I|66|US|29|to2=yes|dir2=south|name2=[[Whitehurst Freeway]]|location1=[[Northern Virginia|Virginia]]}}
|notes=Western terminus
}}
{{DCint
|mile=0.1
|type=incomplete
|road=[[Virginia Avenue]]&nbsp;/ 23rd Street
|notes=Eastbound exit only
}}
{{jctbridge
|mile=0.1
|mile2=0.3
|bridge=Tunnel underneath [[Virginia Avenue]]
}}
{{DCint
|mile=0.3
|road=20th Street&nbsp;/ E Street east
|notes=Eastern terminus; [[at-grade intersection]]
}}
{{jctbtm|keys=incomplete}}