site's layout for its previous use as an airfield is plainly evident. Boca Raton Airport's runway was once part of the original airbase, and is still active to this day, although the runway has been rebuilt. Army School Building #3 (T-604) of the Army Air Forces Base has survived as the office building for the Cynthia Gardens apartment complex on Northwest 4th Avenue. Post-World War II history Boca Raton was the site of two now vanished amusement parks, Africa U.S.A. (1953–1961) and Ancient America (1953–1959). Africa U.S.A. was a wild animal park in which tourists rode a "Jeep Safari Train" through the park. There were no fences separating the animals from the tourists. It is now the Camino Gardens subdivision one mile west of the Boca Raton Hotel. A red wooden bridge and remnants from the Watusi Geyser and Zambezi Falls, a 30-foot waterfall, from Africa USA can still be seen at the entrance to Camino Gardens. Ancient America was built surrounding a real Native American burial mound. Today, the mound is still visible within the Boca Marina & Yacht Club neighborhood on U.S. 1 near Yamato Road. IBM In the late 1960s, IBM announced their intentions to open a manufacturing plant in the area. In 1965, well before the extension of I-95 into Southern Florida, IBM, working in secret with the Arvida corporation, quietly purchased several hundred acres of real estate west of the CSX rail line and northwest of Florida Atlantic University. Originally situated in unincorporated Palm Beach County, the site was annexed into Boca Raton almost a year following its dedication in 1970. Construction of IBM's main complex began in 1967, designed by Marcel Breuer, and the manufacturing and office complex was dedicated in March 1970. The campus was designed with self-sufficiency in mind and sported its own electrical substation, water pumping station, and rail spur. By 1984 IBM was Palm Beach County's largest corporate employer, with 8,500 Boca Raton employees. Among other noteworthy IT accomplishments, such as the mass production of the System/360 and development of the Series/1 mainframe computers, IBM's main complex was the birthplace of the IBM PC, which later evolved into the IBM Personal System/2, developed in nearby Delray Beach. Starting in 1987, IBM relocated its manufacturing for what became the IBM PC division to Research Triangle Park in Raleigh, North Carolina, and converted the manufacturing facilities into offices and laboratories, later producing