New York is a city of layers. Not just the layers below us—the subway tunnels, sewers, and landfill containing trash-turned-artifacts going back 400 years.
The city also has layers on its sides: the rarely visible faded outlines of older buildings that were torn or fell down.
Catching sight of them is like getting a secret glimpse into the city’s past. New development obscures them fast.
One of my favorites is this pattern of what looks like a Federal-style roof on West 15th Street between Eighth and Ninth Avenues (left).
Whatever it was—a 19th century single-family home? A stable?—sat between a townhouse and a tenement until it was bulldozed.
This one on Sixth Avenue and 26th Street below doesn’t look so remarkable . . . but the three chimney outlines and what looks like a roof access area are so well preserved. What was it?

The ghostliest of all is this perfect pattern of a Federal-style house—chimney, roof, and dormer windows all clear—on Hudson and Dominick Streets in Tribeca.

Luckily its twin still stands, letting us know what a little 19th century gem of a home was lost.