Kool Herc played the party that birthed rap on August 11, 1973. At 1520 Sedgwick Avenue in the Bronx, the Jamaica-born Herc played records from the Incredible Bongo Band, James Brown, and other artists whose music would form the backbone of hip-hop. The sound evolved, incorporating more sophisticated blending of records, scratching, eventually MCing.

Outside, the Bronx was in bad shape. Arson was rampant, because slumlords could make more money collecting the insurance from their buildings than maintaining and renting them. The situation in the Bronx, in particular the South Bronx, where hip-hop was percolating, was more reminiscent of a war zone than a place where civilians lived and worked and played. And yet.

Hip-hop blossomed. Watch Charlie Ahearn's Wild Style (one of the 50 best New York City movies), released in 1983, one decade after Herc's legendary party, and you can see every pillar of the culture in full effect: DJing, rapping, graffiti writing, b-boying. These photos, taken in the late '70s and early '80s, give an idea of the physical landscape that birthed this movement.