The Biosphere (La Biosphère), Montreal

The architect of this geodesic dome was Buckminster Fuller. The building originally formed an enclosed structure of steel and acrylic cells, 76 metres (249 ft) in diameter and 62 metres (203 ft) high. It is a Class 1 (icosahedral, as differentiated from Class 2 domes, which are dodecahedral, and Class 3 ones, which are tetrahedral), 32-frequency, double-layer dome, in which the inner and outer layers are connected by a latticework of struts.