In the Mikuni Mountain region roughly 200 kilometres north of Toyko, snow can pile up to a depth of more than five metres in winter. At such times, the science museum resembles a submerged submarine, with the 160-metre-long main section of the building buried beneath the snow and only the 34-metre-high viewing tower remaining visible. Contained within the meandering main tract are the exhibition spaces, a hall for various events, a cafe and research facilities. The route to the entrance leads between high walls of snow. To resist the loading (up to 1.5 tonnes/m2), the outer skin of the building was constructed in 6mm weather-resisting steel sheeting welded in-situ to the structural steel columns and beams. For the execution of this work, the skills of a company specializing in boat construction were required. The enclosing skin consists of two structurally discrete layers, rather like a thermos flask. Subject to temperatures of up to 45?°C in summer, the outer skin was constructed in such a way that it can expand horizontally by as much as 20 cm. This was achieved by creating flexible connections, with stainless-steel panels fixed between the steel columns and the foundations. Although the load-bearing structure is rigidly anchored at only three points, this ensures that the building ultimately returns to its original position.