Watch: This is Why High Avalanche Danger Closes Mountain Roads

Ever driven through the Alps? Drive far enough up just about any major valley, and you’ll find yourself on some of the gnarliest mountain roads in the world, winding their way up scary steep mountain passes. Italy’s 9,000-foot Stilfserjoch is one of those roads, and has gained legendary status as one of the toughest stages of the annual Giro D’Italia road cycling race.

The road is closed in the winter, and for good reason, as it receives feet upon feet of snow on its avalanche-prone slopes. Last week, efforts to clear the road started by explosive avalanche control. Things got out of hand pretty quickly, after a few small point releases propagated into the entire mountainside sliding.