This building, built in 1951, was decorated by famous mexican muralist Juan O'Gorman. Walls are not painted; pictures are made by millions and millions of tiny mosaic stones, making the masterpiece the biggest mosaic in the world (3,317 sq. meters). Every side has one subject. In the photo, western wall, showing university's coat-of-arms, and southern wall, showing the colonial past and ancient concepts of the world (as Ptolomeus and as Copernicus). Pair taken by Juan Voutssas with a Kodak Stereo camera. Kodak Gold print film; ASA 200; speed 1/100; 1/f:11, on july 1997. (voutssas@servidor.unam.mx)