This large complex of buildings situated in the town of Collegno Italy was originally a "Certosa," an Italian word for a Carthusian monastery, or "charterhouse." Construction of the monastery was ordered in 1641 by Christine of France, after King Louis XIII made a pilgrimage to the Grand Charterhouse and vowed to build one near Turin. Grandiose plans were repeatedly scaled back due to financial difficulties, however a grand entrance hall was constructed by the architect Filippo Juvarra in 1725.
With the annexation of the Napoleonic empire in 1802, the Carthusians were forced to disband, and the property passed through a number of private hands and also suffered extensive damage and looting. When the charterhouse was reopened in 1818, the monks residing here had become increasingly scarce. The space would not be empty for long - in 1850 the public administration placed 50 insane patients at Collegno, to relieve an overcrowded asylum nearby. Soon after 100 more patients were transferred; eventually the monks would have to leave due to a law that eliminated certain religious communities.
Pressed for time and lack of funds to construct a new asylum for Turin, the premises was wholly taken over by Regio Manicomio (Royal Asylum) in 1855 for use as a psychiatric hospital. It was a difficult start since the layout was not optimal for psychiatric care, and a cholera epidemic in the previous year had claimed many lives. Eventually, many additional buildings were constructed to accommodate the steady influx of patients - there were over 1,700 in 1928. By the 1940s, the hospital consisted of over twenty pavilions, connected by long arcades under which a small railroad operated, called Decauville.
In the 1920s, the hospital was the beginning scene of an interesting event called Smemorato di Collegno (the Collegno Amnesiac) - the term would become popular in the 1930s to describe someone who is forgetful. The story: Professor Giulio Canella was missing in action during WWI, and was presumed dead until his wife recognized his photograph in a newspaper article, describing a hospital patient who had lost his memory. After visiting the patient at Collegno, the wife was convinced that this person was her lost husband; the man was eventually released and the couple lived together and had three children. An anonymous letter was received upon his release describing him not as the lost Professor Canella, but of Mario Bruneri, an anarchist with an extensive criminal record. After an extensive investigation and many trials, the "forgetful man" was identified as Bruneri, however the wife was convinced she was living with her lost veteran husband. Escaping the public opinion on the scandal, the couple moved to Brazil and stayed for the rest of their lives; attempts to have the decision overturned were denied. The details of the case can be read here.
A slow de-institutionalization process began in the 1980s. Most Italian psychiatric hospitals were ordered closed, including Collegno, in December of 1996; however around 450 patients still reside on the grounds. Some buildings were abandoned, while others were re-purposed for use as municipal offices, health services, and university classrooms. A large wall surrounding a criminal building was demolished, and the vast gardens and open spaces are used as a public park.