The Cathedral of Saint Mary of the Assumption in San Francisco, designed primarily by Pietro Belluschi and Pier Luigi Nervi, is a structural feat of engineering and a bold Modernist design from the early 1970s. Despite its simple square plan, the roof of the cathedral rises into four parabolic hyperboloids, which are given a seeming weightlessness by their vertical separation from the floor and their lateral separation from one another. Four pylons raise the cupola, and brilliantly colored stained glass separates the cupola fragments, giving the nave a sense of effortlessness. The Cathedral is now one of San Francisco's best-loved structures, attracting parishioners and tourists alike. Although the physical form was controversial to some upon its construction, Saint Mary's Cathedral is now a clear representation of the Modernist movement, evidenced by its radical use of precast concrete forms and non-traditional religious design.