Professional kayaker Adrian Mattern descends down a huge 90ft waterfall in Oregon.br br Filmed on April 12, Mattern with a GoPro strapped to his head edges towards the water's edge before plunging down the 90ft drop.br br Another angle, filmed by a drone, shows the sheer height of the Abiqua Falls as the German daredevil drops down the waterfall.br br Mattern is renown for undertaking various stunts on his kayak such as racing down a storm drain in Norway at 50mph.