Viewed from the sky, strange cleavages appear along the urban fabric of Los Angeles and San Francisco, like the image above, of a former Southern Pacific rail line arching through the Mission District in San Francisco. (See in Google Maps. More on this route: Nesssoftware.com)

They’re the result of long-lost rail lines, a sort of architectural scar tissue in the form of alleyways and property lines. In the starkest examples, the trajectories plow diagonally through the neat grids of whole neighborhoods, skewing the shapes of buildings, fences, and parking lots. Below is a former Pacific Electric line slicing between West Hollywood and Sunset Boulevard in Los Angeles. (See in Google Maps. More about this route:  Hollywood Partnership)

“The notion that every city has these deeper wounds and removals that nonetheless never disappear is just incredible to me,” wrote Geoff Manaugh, an architecture blogger. “You cut something out — and it becomes a building a generation later. You remove an entire street — and it becomes someone’s living room.” 

Read more: BldgBlog | 99% Invisible 

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