Railroad apartment

The term railroad apartment describes a lay-out that is analogous to that of a typical (mid-20th century or earlier) passenger train car. Such cars had compartments (typically holding 4–6 passengers) accessed by a narrow hallway running along one side, along their entire length. The analogous apartment has a series of rooms that are accessed from a hallway that runs the length of the apartment from the front to the back door. This usage is most common in New York City, San Francisco, and their surrounding areas. Railroad apartments are common in tenement or even modern apartment buildings, and are sometimes found in subdivided brownstones.