The Launch Complex 39 launch pads (39A and 39B) are located approximately 3 mi. (5 km) from the Vehicle Assembly Building. Each launch site is an eight-sided polygon approximately 3,000 ft. (1 km) across. At the center of each complex was raised concrete launch structure. A ramp with a 5% slope leads from the crawlerway to the top of the launch structure. Pads 39A and 39B were essentially identical during the Apollo program.

Apollos 4, 6, 8, 9, 11, 12, 13, 14, 15, 16, 17, and the Skylab Orbital Workshop were launched from pad 39A.

Apollo 10, the Skylab manned missions, and the Apollo-Soyuz Test Project were launched from pad 39B.

Both LC-39 launch pads were heavily modified for the Space Shuttle Program. LC-39B was further modified to support the Ares 1-X test launch in 2009. After the Ares program was cancelled, 39B was reduced to a 'bare pad.'

Pad 39A was leased to SpaceX in 2013 and will be converted to support their launches. Since it is a National Historic Landmark, the structures inside the pad must be maintained.