Space Launch Complex 3 (SLC-3) is a launch site at Vandenberg Air Force Base that has been used by Atlas and Thor rockets. It was built in the early 1960s and consists of two pads, SLC-3E (East) and SLC-3W (West). The East-West coastline at Vandenberg allows SLC-3 to launch over-ocean polar trajectories that avoid landfall until passing over Antarctica.