District of Columbia/Maryland Route 295
Length: 40 miles (estimated)
Termini: I-95 exit 52 in Baltimore, 11th St. Bridge in Washington
Reason for being a state route: The Baltimore-Washington Parkway (sometimes called the Baltimore-Washington Expressway) is maintained by the National Park Service; beauty would be sacrificed for interstatedom in this case. South of I-595 (US 50/301) and as Kenilworth Avenue, the road is horrible, Pennsylvania-standard stuff, explaining why it is not I-295 until after the 11th Street Bridge. (But I-295 IS interstate from 11th St. south. On another note, I-695 would have not connect to an interstate if built north of the Barney Circle, but since DC 295 was to have been upgraded into a northern extension of the Anacostia Fwy., it would have been logical.)
History: This route has existed before I-95 came into being, although I do not know exactly when. It was already TEMP I-95 in the 1960s, as I-95 was to have been built into downtown Washington (but never was, although Douglas Willinger (dougwill@idt.net) has been working to revive the idea, with some underground freeways.
Kenilworth Ave. is a horrible mess of a non-standard freeway. Poor pavement, poor shoulders--this is what exemplifies PA 666, or any other Pennsylvania road. Washington corruptness may explain for this road.
However, the Baltimore-Washington Parkway is maintained by the National Park Service, which leads me to believe that this is a beautiful route between the two cities, as compared to I-95. But it is also not interstate standard.