Five “tree houses” are scattered about the woods of Harads in Sweden, and more are planned. These unusual hotel units, 15–30 m2 in size, can accommodate two to four people.  The outer skin of “Mirror Cube” reflects the forest and the sky, thus helping to integrate the space into its environment. Guests reach their retreat via a slender bridge, while a ladder rises from the living room to the roof terrace. The skeleton frame consists of two prefabricated aluminium elements. The four-tonne cube is fixed to the trunk of a large fir tree by adjustable clamps and stayed with cables. Its good insulation, its underfloor heating and the plywood inner lining create a cosy atmosphere, even when temperatures are low.