The Igloo Village of Hotel Kakslauttanen in Finland boasts 20 thermal glass igloos that allow visitors to enjoy incredible views of the Aurora Borealis from the warmth and comfort of their own geodesic hut.
La Conciergerie. Build in the Middle Ages as a Merovingian Palace, it was later converted to a prison when Charles V decided the Louvre was much better digs. It had a bit of a notorious reputation, from the torture, to its roll as a holding cell for prisoners before meeting the guillotine during the reign of terror. This staircase is located in the main hall and leads up to the upper stories