If you’re the type who’s prone to claustrophobia, then a sleepover in one of these holes is not a good idea. The Dasparkhotel in Austria and Germany are a new trend that’s recently hatched. While the novelty factor in them is high, a lot of blokes might not be too cozy with sleeping in structures destined for sewers. Yes, each ‘unit’ in the hotel is made of concrete drain pipes. Unused concrete drain pripes (fortunately).