the bronx
Main articles: East Coast hip hop, Music of New York City
New York City (specifically the West and South Bronx) was the birthplace of hip hop, in 1973 and all of its prime early movers, such as DJ Kool Herc, Grandmaster Flash, Caz and Afrika Bambaataa grew up and began performing there.
http://en.wikipedia.org/wiki/American_hip_hop