As you walk along the streets in Washington, D.C., you'll notice that signs at corners give not only the street name but also a numerical indicator representing the numbers assigned to a given block—typically in multiples of 100.
So, as you approach the U.S. Capitol, you're likely to see signs saying 500, 400, 300, 200, 100. Then what happens? Do you get 000 or 00?
Curiously, the chosen designation for the zero-order block is UNIT.
I wonder how this designation came about (and whether it even makes sense in this context). So far, I haven't been able to find anything on its history. And what happens in other cities?
My thanks to Joshua Zucker for pointing out this unusual feature of the Washington streetscape.
Photos by I. Peterson