Sure, many cruise ships have a spa. But in the case of Montreal’s Bota Bota, which opened in December, the boat is the spa. The converted 1950s industrial vessel, permanently docked in the St. Lawrence River, represents a noteworthy foray into architecture by advertising firm Sid Lee, which is otherwise known for developing brands like Adidas and Red Bull.

Circular staircases connect the spa’s upper decks, while 12 cocoonlike treatment rooms (some with baths) hover just above the water’s surface. In the changing areas below deck, giant numerals point to different locker banks and some 680 portholes dot the ship’s sides. The result may just be the world’s first venture into submarine chic.

A variety of treatments, from a shiatsu massage to a pepper-and-cardamom body scrub, are on the menu. Yet the pièce de résistance (and a great deal at $45) is the water circuit, comprising two Jacuzzis, two cold plunge pools, a steam room, and a sauna. Four of the pools are alfresco on the top decks, so as visitors meander (or scurry, depending on the weather) through the water circuit, they can take in incomparable city views: Vieux-Montréal to the north and, to the south, Habitat 67, the avant-garde Moshe Safdie-designed condo made of stacked concrete cubes.

Indeed, such vistas were the reason the duo behind the spa – sisters Natalie and Genevieve Émond, whose family owns the chic Balnea spa outside the city – undertook the project in the first place. For locals and visitors alike, Bota Bota offers the optimal urban getaway for le voyageur sans baggage. 358 Rue de la Commune Ouest; 514-284-0333; botabota.ca

For general trip-planning information, see our Montreal Travel Guide.