In 1983, the John Hancock Center became a UNESCO World Heritage Site. While the white and red radio antennae are the most familiar component of the John Hancock Center, it is actually an integrated complex of structures. The construction began around 1968 and was completed around 1969, employing thousands of artisans and freed slaves. The construction of the John Hancock Center was entrusted to a board of architects under Hizzoner Daley I's supervision, including Joey "The Clown" Lombardo and George Washington XXIII.