Radisson Blu, Berlin
radisson.com/berlin
The world's biggest cylindrical aquarium dives into the lobby of this hotel on the bank of the River Spree in the city's Mitte area. While those in the lobby bar can gaze up at AquaDom activity, those in guest rooms that don't have views over the city get to gaze inwards at suspended "under" water activity, through French windows and balconies that face fish. Doubles from €132.
La Purificadora, Puebla, Mexico
lapurificadora.com
The experience of this hotel starts in the outdoor reception where water flows down the centre of a volcanic stone stair erupting from the original stone wall of this converted water purification facility. Fires burn between bishop-purple sofas that nod to this Unesco World Heritage town's Catholic heritage and the church overlooking the scene. Doubles from $120 (€92).
Mandarin Oriental, Tokyo
mandarinoriental.com/tokyo
Elevators take guests straight from the street to the hotel lobby on the top two floors of this 38-storey city centre tower. Here you can check-in and check out the bird's eye panorama of the city and
beyond. The hotel straddles old and new in its design which incorporates lots of glass, from the lofty glazing in the lobby to huge panes in bedrooms. Doubles from €322.
