The Howard Hughes Professional and Aeronautical Photographs contain black-and-white photographs of businessman and entrepreneur Howard Hughes and his companies from 1916 to 1997. The photographs primarily depict Hughes alongside his aircraft, including the XF-11 prototype reconnaissance plane and the HK-1 Hercules, better known as the "Spruce Goose" or "Flying Boat." The photographs also cover the companies owned by Hughes, including Hughes Tool Company, Hughes Aircraft Company, Hughes Electronics Corporation, and RKO Pictures.

The collection is comprised of records of the San Pedro, Los Angeles & Salt Lake Railroad Company (1901-1976). The construction of this railroad led to the founding of Las Vegas, Nevada and the creation of the Empire Construction Company and Las Vegas Land and Water Company. The records document the company's operations and include correspondence and contracts relating to lots in the Las Vegas townsite, payments and accounts, invoices and other audit materials from 1905 to 1923. The collection also includes the records of the railroad agent at Arden Station, located ten miles south of the Las Vegas Station, which contain correspondence, ledgers, freight and way bills, shipping orders, and telegrams.