At the centre of the exhibition, two concrete cuboid sculptures occupy the gallery’s main space. Grotto-like interiors are visible inside the cubes through irregular openings in their smooth concrete walls. Formed by casting blocks of ice in concrete, the sculptures are indexical traces of the now - melted ice, only present as absence. Eliasson brought the ice from the Greenland ice sheet, which was formed over millions of years by layer upon layer of highly compressed snow, and placed it in a casing at his studio.
Concrete was poured into the casing and the ice was left to melt away over a period of about a month. The melting ice produced sounds like miniature explosions as it carved out voids within the cubes and punctured holes in the concrete walls, leaving only the memory of the ice within the artwork.