The Prague Pneumatic Postby Sam Beckwith
It sounds (and looks) like something from a steampunk sci-fi novel but the Pražská potrubní pošta (Prague Pneumatic Post), a 55-kilometer-long network of underground air-powered delivery tubes, really exists.
Dating back to the late 1880s, the system enabled metal capsules containing letters, telegrams, documents and even food to be delivered between the city’s main post office, on Jind?išská street, and branches and other offices across the city:
The pneumatic post remained a popular way of delivering urgent messages for most of the 20th century but demand dwindled in the 1990s and the system was severely damaged by 2002′s floods.
According to an article published in the Pražský deník newspaper in March 2009, the system was no longer in active use but current owners Telefonica O2 were continuing to maintain it and considering some sort of further use for it.