^* BASE stands for Building Antenna (radio tower) Span (bridge) Earth (cliff)—the four dangerously low things they parachute from. According to a 2007 Journal of Trauma study, the death and injury rate for BASE jumping is five to eight times that of skydiving. Though it’s lower than you’d think: 9 out of 20,850 jumps off Norway’s Kjerag Massif over a ten-year span (run of years) have ended in death.