The operators of this zipline in Sarangkot, Nepal call it "the world's most extreme" example of its kind. Judging by this video, their claim is legitimate. Boasting a vertical drop of 656 yards and stretching over a mile, ZipFlyer Nepal is extremely steep, long, and very, very scary. It's also extremely fast: A ride on this baby could see you race along at up to 87 mph. At least if you're too chicken to ever ride this zipline, you can use the excuse that it's too far away.