The design and architecture of the Haltia building were inspired by a poem from Finland's national epic, the Kalevala, which tells the story of the world's creation. According to the poem, in the beginning, there was only water and air. Ilmatar, the maiden of the air, grew lonely and descended into the primordial sea. A goldeneye duck, seeking a nesting place, made its nest on Ilmatar's knee and laid six golden eggs and one iron egg. As the eggs were incubated, Ilmatar's knee became hot, causing her to shift, and the eggs fell into the water and broke. From the pieces, the earth, sky, sun, moon, stars, and clouds were formed.

Haltia resembles the duck brooding over its eggs. The building's tower resembles the neck of a bird, and the bird's head is turned to look at Lake Pitkäjärvi. The solar panels on the roof resemble the feathers of a bird. The duck's egg can ultimately be found in Haltia's main exhibition. The building transforms knowledge into an experience, surrounding visitors with a world of legends and myths where ancient Finnish nature and contemporary nature coexist. The inspiration for everything is Kalevala's cultural heritage.

Haltia fits naturally into the steep hillside and landscape, much like a bird in its nest. The architecture of Haltia blends curving, free-form lines with rectangular, rational shapes, symbolizing the meeting of nature and the human-made environment. Through the interplay of curving and straight lines, Haltia showcases various dimensions of wood construction: the possibilities of wood joinery, on-site construction, and pre-fabrication techniques that favor straight lines, as well as traditional and modern wood treatment methods.

Haltia's northern side is sheltered within the rock, embodying the symbolism of the north: cold, darkness, and retreat. The southern side of the building, however, reaches out towards the lake landscape, embodying the symbolism of the south: openness, light, and warmth.

The soft shape of the northern wall line allows Haltia to nestle into the rock's embrace. Within the space defined by the curving wall are Haltia's exhibitions, which also encapsulate the original architectural idea: the Kalevala creation story and the duck's egg. Haltia's tower reaches into the air like the neck of a bird.