BASE jumper Alexander Polli recently flew through a hole no more than six feet across while on a trip in the Roca Foradada Mountains of Montserrat, Spain. BASE jumping is already a little more than dangerous, but the added risk of making it through an opening that small is almost unbearable. Combining footage taken from his helmet and from the ground, Polli's video of his jump is simply amazing, and it's hard to imagine he reached speeds upwards to 155 mph. 

 [via Mashable]