The Prague Pneumatic Post

The City of Prague has a system of pneumatic tubes to send mail from one place to another, like New York City and Paris once had. The difference is that Paris discontinued sending mail by tube in 1984, and New York ceased in 1953. People in Prague could send mail across town by tube until 2002!

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.

I hope they will be able to preserve the 55-kilometer system for posterity. Link -Thanks, Jeff!