A railroad apartment is an apartment with a series of rooms connecting to each other in a line.[1] A hallway typically runs the length of the apartment or flat from the front door to the back door, outside each room.[2] This is similar in design to a railway car. This usage is most common in New York City, San Francisco and their surrounding areas. Railroad apartments are common in brownstone apartment buildings.
Sometimes confused with a shotgun house, which is just a series of rooms connected directly, with no hallway, railroad apartments do typically have hallways.[2] However, rooms may also connect directly, such as with panel doors that connect the living room to the dining room.[2]
Railroad apartments first made an appearance in New York City in the mid-19th century, and were designed to provide a solution to urban overcrowding.[3] Many early railroad apartments were extremely narrow (some only 20 feet wide), and most buildings were five or six stories high.[3] Few early buildings had internal sanitation, and bathrooms emptied raw sewage into the back yard.[3] In some cases, one family would take up residence in each room, with the hallway providing communal space.[2]