Secrets of the Taj Mahal - More Than An Architectural . Masterpiece. Smithsonian video. Taj Mahal. Agra, Uttar Pradesh, India. Masons, marble workers, mosaicists, and decorators working under the supervision of Ustad Ahmad Lahori, architect of the emperor. 1632–1653 C.E. Stone masonry and marble with inlay of precious and semiprecious stones; gardens.