BASE jumping is named after the four things you leap from

BASE jumping takes its name from an acronym: Building, Antenna, Span (a bridge), and Earth (a cliff). Instead of leaping from an aircraft like a skydiver, a BASE jumper leaps from a fixed point and deploys a single parachute to reach the ground.

Because the jumps happen from such low altitudes, there is far less time to correct a problem or open a reserve. That makes BASE jumping much more hazardous than ordinary skydiving - widely considered one of the most dangerous extreme sports - and, partly because of the risk to people below, it is usually illegal.

The term was coined by filmmaker Carl Boenish, regarded as the father of the modern sport, who in 1978 filmed the first systematic jumps from Yosemite’s El Capitan. Boenish died in 1984 after a jump from Norway’s Troll Wall. Many jumpers now wear wingsuits, gliding far across the sky before opening their canopies.