Perched on top of a Balkan mountain peak, this strange monument, which was abandoned many years ago and now stands in ruins, has recently acquired something of a cult following.
Originally designed in the 1980s as a congress hall for Communist Party conventions, the "Flying Saucer," as Bulgarians refer to it, is in most international books for alternative travel, spooky locations Internet sites, urban decay research reports and guidebooks for Austrian bikers.
Access to it has been banned as the building is considered dangerous, but many still find their way inside to view the surreal destruction in its great hall or the stunning views from the top.
A visit there is a must before the Flying Saucer collapses completely – or is turned into a luxury hotel.
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