At Twin Falls, Idaho, the Perrine Memorial Bridge spans the Snake River Canyon. The bridge is 486 feet above the Snake River and is currently the eighth highest bridge in the United States. The bridge is a popular BASE jumping site and BASE jumping is allowed year-round without a permit.
BASE jumping involves parachuting or wingsuit flying from a fixed structure or cliff. BASE is an acronym standing for: Building, Antenna, Span, Earth. In general, BASE jumping is more dangerous than skydiving and is illegal in many locations.