Set on Helsinki’s South Harbor which is a part of Finland’s nationally significant coastal landscape, the museum translates the meeting of the shoreline and water into architectural forms. The design is an exploration of programmatic intersections between sharp rectilinear volumes and encapsulating curved shells. Like waves carving rock or sails catching wind, the curves wrap, bridge, and shade the boxes, producing a form that transitions the city into the water. At 100,000 sqft, the program integrates permanent and temporary exhibitions, archives and conservation labs, learning studios, a public atriums, cafés/shops, events, and outdoor rooms. A central axis aligns the city, plaza, atrium, and gallery decks with public circulation that compresses, flows, and expands on the interior. Museum visitors pass a narrow entrance and emerge into a daylit atrium from which a cantilevered glass-and-steel gallery projects over the harbor, extending the museum’s reach into the harbor. The design intentions and requirements are balanced through a robust yet resource smart strategies. Using engineered timber and primary/secondary steel frames on top of concrete cores and foundations; a space-frame skylight with cable assists for long spans; and a curved stud/shell system creates the fluid envelopes while delivering acoustic control, integrated ventilation, and concealed drainage. Galleries are modular using hanging grids, demountable walls, and black-out/white-box modes, meeting curatorial flexibility. Because of the site location, constraints such as public shoreline access, protected view cones to the historic center, harsh maritime climate, and pedestrianization goals, shape the massing. The form of the museum sits low to maintain view corridors, the curved shells rise where shading, wind buffering, and snow shedding are needed, and the ground plane remains accessible to preserve the waterfront promenade. Materials address salt spray, freezing and thawing, and corrosion with stainless fixings, marine coatings, laminated timber species, and warm-edge glazing. The environment of the project heavily influences the architectural expression: deep overhangs and sail-like forms provide shade, skylight zones modulate daylight, and the huge atrium vents support passive ventilation. Timber sequesters carbon; optimized steel trusses and minimized concrete reduce embodied impacts achieve energy efficiency and carbon reduction. This project advances Helsinki’s ambition to be a design-driven city. It unites the legacies of the Museum of Finnish Architecture and the Design Museum in a structure that is both an exhibition machine and public space. The result is a distinctive, feasible, and future-ready museum: precise where it must be, fluid where it should be, and unmistakably of the harbor.