A backlot is an area behind or adjoining a movie studio, containing permanent exterior buildings for outdoor scenes in filmmaking or television productions, or space for temporary set construction.
Some movie studios build a wide variety of sets on the backlot, which can be modified for different purposes as need requires and "dressed" to resemble any time period or look. These sets include everything from mountains, forests, ships, to small town settings from around the world, as well as streets from the Old West, to whole modern day city blocks from New York City, Paris, Berlin, and London. There are streets that comprise an assortment of architectural styles, Victorian to suburban homes, and 19th century-style townhouses that encircle a central park with trees. An example of this is "Forty Acres" in Culver City, California or, in the case of Universal Studios, the home of Norman Bates from the Hitchcock movie Psycho.
The shells, or facades, on a studio backlot are usually constructed with three sides and a roof, often missing the back wall and/or one of the side walls. The interior is an unfinished space, with no rooms, and from the back of the structure one can see the electrical wires, pipes, beams and scaffolding, which are fully exposed. Ladders are usually built into the structure, allowing performers to climb to an upper-floor window or the roof to do scenes. Not all the buildings and houses are shells, however. Some are closed in with a fourth wall. When not otherwise in use, they double as storage facilities for lighting and other production equipment. When in use, the structures are dressed by adding doors, window treatments and landscaping. L-shaped temporary walls are placed inside of doors to give the illusion of an interior. When not in use, however, the structures are usually stripped of this dressing.
Mel Brooks' Blazing Saddles offers a rare look into the Warner Bros. backlot, with scenes spilling off the Laramie Street set into various stages and eventually out of Gate 3 onto Olive Blvd. in Burbank, California. Television shows such as Moonlighting and It's Garry Shandling's Show also broke the fourth wall and gave audiences a peek of life on the other side of the camera.
All the sets on a studio backlot are built so that what looks large or as if it covers miles of ground on the big or small screen in reality only takes up a few acres of the backlot.
Today many studio backlots are gone or nearly gone as Los Angeles real estate prices and more location filming have driven the sale of the backlots to developers. In their heyday, some backlots covered hundreds of acres around existing studios and filmmakers rarely left the lot. Though some studios like MGM and Fox sold vast tracts in the '60s and '70s, many historical sets continue to be razed even now as there seems to be little interest in their preservation. Most recently, the western town set of Warner Brothers, used in TV shows Bonanza, The Waltons and films like Wild Wild West have been razed and repurposed into office space.