The Presidio Modelo was a “Panopticon”* design prison in Cuba. The design allowed all the inmates to be watched by a single watchman without the inmates being able to tell whether or not they were being watched; ca. 1926
The Panopticon is a type of institutional building designed by the English philosopher and social theorist Jeremy Bentham in the late 18th century. The concept of the design is to allow all (pan-) inmates of an institution to be observed (-opticon) by a single watchman without the inmates being able to tell whether or not they are being watched. Although it is physically impossible for the single watchman to observe all cells at once, the fact that the inmates cannot know when they are being watched means that all inmates must act as though they are watched at all times, effectively controlling their own behaviour constantly. The name is also a reference to Panoptes from Greek mythology; he was a giant with a hundred eyes and thus was known to be a very effective watchman.
This prison is not a true Panopticon design.
No true Panopticon prisons to Bentham’s designs have ever been built. The closest are the buildings of the now abandoned Presidio Modelo in Cuba (constructed 1926–28). Although most prison designs have included elements of surveillance, the essential elements of Bentham’s design were not only that the custodians should be able to view the prisoners at all times (including times when they were in their cells), but also that the prisoners should be unable to see the custodians, and so could never be sure whether or not they were under surveillance.
“This objective was extremely difficult to achieve within the constraints of the available technology, which is why Bentham spent so many years reworking his plans. Subsequent 19th-century prison designs enabled the custodians to keep the doors of cells and the outsides of buildings under observation, but not to see the prisoners in their cells. Something close to a realization of Bentham’s vision only became possible through 20th-century technological developments—notably closed-circuit television (CCTV)—but these eliminated the need for a specific architectural framework.