There's a recent fun post at the Australian blog The Conversation that looks at old mines and surface facilities that were converted into other uses such as stores, hotels, wedding chapels, classrooms, biofuel plants, storage vaults, and so on. Examples are from all over the world. [Right, Cricova, Moldava limestone mine used as a wine cellar. ]
Here in the U.S., former underground salt mines in Kansas are used to store bank records, original copies of Hollywood movies, and specialty items requiring constant temperature and humidity. The old Homestake gold mine is slated to become an underground physics lab.
The blog post alerted me to the existence of the Post-Mining Alliance, "an independent, not-for-profit group, based at the UK’s Eden Project - itself a former clay mining pit transformed into an environmental tourism attraction and educational charity."