The gallery's modernist main building, built from 1947-1953, was among the first designed by Louis Kahn, who taught architecture at Yale.("Kahn played a major role in Yale's own artistic development. And Yale in turn would give Kahn the commission that transformed his career as an architect.") Although the Art Gallery with steel structure and reinforced concrete may seem simple to the eye, it was designed in a rigorous process. Kahn and Anne Tyng, the first woman licensed as an architect in the state of Pennsylvania and an employee of Kahn's independent practice, "devised a slab that was to be poured into metal forms in the shape of three-sided pyramids. When the forms were removed, they left a thick mass of concrete imprinted with tetrahedral openings." The triangular ceiling of the gallery was designed by Tyng, who was fascinated by geometry and octet-truss construction.