Utter Inn -- Västerås, Sweden
Designed by artist and sculptor Mikael Genberg, the Utter Inn is really an art project: Guests are dropped off at a typically Swedish-style mini house on the water's surface, then left to their own devices. Literally a reverse fishbowl, the 80sqft, single-room property is nothing but two twin beds, a table, a bathroom, and a camping stove.
Depth: 10ft
Rate: Around $167/nt
Most exotic fish that'll stare disapprovingly at you through the glass: This ain’t the tropics -- expect perch and pike, and lots of ‘em.