Starting in 1977, Vergara, who was awarded a MacArthur Foundation genius grant in 2002, has documented the facades, interiors, and streetscapes of numerous American cities, but the website encompasses only three -- Harlem, NY; Richmond, CA; and Camden, NJ. As the buildings age from era to era, they lose their 19th century details and gain and drop signage along the way, while the cities that surround them crumble and swell in concert with the economy.

Vergara's site is chock-full of academic text and an interactive design complex enough that the landing pages offer unsolicited instructions on how to use its tools. The use of mapping allows visitors to scan images according to geographic location as well as the type of photograph (panoramic, street view, detail, etc). But you can also take a simple approach just by diving straight into the photos. When you first click on the Harlem, NY database, you'll get a view of 65 East 125 St. as it looked every couple of years from 1977 through 2007, morphing from a funky gin-joint called the "Purple Manor" to a generic, shuttered mattress store today. (Be sure to click through to the full-size images, and be amazed at how old-school film can be digitally translated.) Select any of the tiny squares on the Harlem map to move around the neighborhood and examine its transformation from many angles and distances.

While Vergara's stated goal for the Invincible Cities project is to document the fall and rise of what he calls the "American ghetto," it's also a collection of stunning photos that practice the best kind of architectural history. As with people, what these buildings have gone through over their long, storied lives is written all over their faces.

All images from Camilo José Vergara's website.