Open up Google Maps, visit Providence, zoom in at the highest resolution, and scroll around the Brown campus area. You'll see a grey zone covering the Brown University Athletic Complex, just south of a local maximum in the East Side's undulations.
I recently compiled a Google Maps mash-up of the restaurants on and around Thayer Street. This resulted in a long, thin map of the Thayer area, at the top-right of which were the letters "D" and "A" on two separate lines.
I spent a few moments wondering what this might stand for. Nothing came to mind, so I scrolled the map...to find the legend "Dexter Asylum"!
Was this a prank by one of our alums? Was this a Mountweazel?
Neither, it turns out. There was indeed, on that very site, an institution by that name. A wonderful article on the Rhode Island Historical Society Web site says that the it was an ``institution for the care of the poor, aged and mentally ill of Providence from 1828 to 1957''; the residential growth of the East Side put an end to it.
The question remains, how come it's on one map and not the other? As Pete Hopkins pointed out, as of this writing, Google Maps uses NAVTEQ whereas the API uses TeleAtlas. Sure enough, blogspace is alive with comparisons of the two; a common opinion seems to be that NAVTEQ's data tend to be newer and more accurate, but I am no authority.