Lignum is the Swiss information centre concerning the use of wood. Frei + Saarinen Architekten were asked to design an exhibition pavilion that shows a contemporary use of wood for architectural purposes.The Lignum-Pavilion is not more than a walkable pile of 20 layers that consist of 50mm-thick planes and vertical elements of 130mm height. Similar to a pixelated image, these 20 layers form an architectural body that leads the visitors through a promenade architecturale in the shape of a spatial "figure eight".All 541 wooden pieces are cut by a cnc mill. The pavilion will be used ten times during the period of three years. It will be shown at the "Swissbau 2010"-fair in Basel, too (12.01.-16.01.2009).