A decommissioned 1951 ferry moored at Montreal's Old Port now holds five thermal pools, a sauna carved into former engine rooms, and massage tables where cargo once sat. Bota Bota opened in 2010, the product of a decade-long conversion that preserved the vessel's industrial bones while inserting hydrotherapy infrastructure. The boat remains tethered to Quai de la Commune year-round, drawing heat from shore-based boilers and draining into municipal wastewater systems. No engine turns. The movement visitors feel comes from the St. Lawrence current nudging the hull. The massage boat Montreal model emerged from Quebec's broader spa industry, which generated 1.2 billion CAD in annual revenue by 2020. Bota Bota anchored the waterfront wellness corridor that now stretches from Pointe-à-Callière to the Clock Tower Beach. The floating format solved azoning problem: Old Montreal's heritage district restricts new construction, but marine vessels fall under federal jurisdiction. The spa's designers installed floor-to-ceiling windows along the starboard promenade, framing views of the Bonsecours Market dome and the Jacques Cartier Bridge's cantilevered span. Winter operations required custom engineering. Ice formations on the St. Lawrence can exert 200 tons of pressure per square meter; the boat's hull was reinforced with steel plating and fitted with pneumatic fenders that flex under load. The water circuit follows a Scandinavian thermotherapy sequence: hot pool, cold plunge, rest. Each cycle lasts 20 minutes. The top deck holds a shallow relaxation pool heated to 40°C, positioned to catch southern sun exposure. One level down, a eucalyptus steam room occupies the former captain's quarters. The cold plunge, fed by municipal water chilled to 10°C, sits amidships in what was once a cargo hold. Massage treatments use a booking system separate from circuit access. Therapists work in 12 treatment rooms distributed across three decks, each soundproofed with marine-grade insulation. The most requested service is the 90-minute deep tissue session, which incorporates arnica oil and hot stone applications. Appointments fill fastest on weekday mornings, when the boat's capacity of 250 guests rarely peaks. Weekend afternoons see queues at the reception desk. Bota Bota's operational model influenced subsequent floating spas in Copenhagen, Auckland, and Vancouver. The Montreal vessel remains the largest by square footage, with 2,300 square meters of usable spa space. The boat's draft—3.2 meters—limits access to deep-water berths. Relocation would require tugboat assistance and port authority permits. For now, the spa stays put, a fixed point in a shifting river, its gangway connecting thermal baths to cobblestone streets.