[upbeat rock music] - time sinks slowly to the deepest part of the ocean-- the mariana trench. she's tired of light, and there it's pure black. bourdain: they say that butte is a mile high and a mile deep, and to get an idea of what they mean, you've got to go down-- down deep into the hill. an intricate warren of tunnels riddled through the rock and soil that lay beneath the city was flooded forever by water and darkness. the orphan boy mine is one of the few remaining hard-rock mines in the city.