A long time ago, before the Beltway and the Interstate highway system, a web of U.S. highway routes crisscrossed the nation, connecting cities, towns and villages. These U.S. highways still exist, but now only form the backbone of the nation's secondary federal highway system. Route 1, which passes through D.C. via Rhode Island Avenue and the 14th Street Bridge, links Maine and Florida. Route 50, coming straight down Consitution Avenue, links Ocean City, Md., with Sacramento, Calif.

Then there is Route 29, the bastard child of highways passing through the District. While it enters the city via the Key Bridge and Georgia Avenue, its routing between those two points is at best imprecise. The District Department of Transportation doesn't seem to know where it goes either, as it has signs for the highway at different points in the city going in very different directions.

Pedestrians and drivers passing through Dupont Circle have most likely seen this sign pictured above. Route 29 passes around the circle with New Hampshire Avenue as its entry and exit points. But if you happen to drive north or south on New Hampshire Avenue from the circle (as the routing signs point to), Route 29 disappears.

But if you're on the Whitehurst Freeway heading toward K Street, a large overhead sign indicates Route 29 runs across town via Gucci Gulch. Other signs over on Georgia Avenue indicate it runs through town that way. So what gives? If you were traveling from the highway's starting and ending points -- Pensacola, Fla., and Mount Hebron, Md. -- how would you travel through the District on the phantom highway?

Well, begin on the Key Bridge for starters, where Route 29 crosses the Potomac after weaving its way through Arlington County on Lee Highway. But once you cross the bridge, there's trouble. The turnoff for the Whitehurst Freeway at the end of the bridge is not marked, as you can see from these DCist photos taken last month.

From current maps, it appears that from the Whitehurst Freeway, Route 29 crosses town on K Street to 11th Street NW to Rhode Island Avenue to Seventh Street NW to Georgia Avenue and on up to Colesville Road in Maryland.

So where does the New Hampshire Avenue routing come in? According to older maps we've seen from the late 1940s, Route 29 cut up New Hampshire Avenue from Washington Circle through Dupont Circle to 16th Street, where it went up to Alaska Avenue to Georgia Avenue. The Route 29 signs at Dupont Circle are either really old (though they don't appear to be that old) or DDOT seems to believe that Route 29 runs via the old routing.

From a DCist source who lives on New Hampshire Avenue near T Street NW:

Since New Hampshire Ave. switches from two-way to one-way at T St. (where I live), there seems to be more traffic turning left onto T from New Hampshire, as all the north-bound traffic has to dog-leg over to 16th to keep heading north. I also know from guests arriving from out of town that trying to come into to the city on New Hampshire is ridiculously difficult. For much of its' length it's barely an avenue, let alone a highway.