Getting to Schiek's Cave, located 75 feet below Schiek's Nightclub in downtown Minneapolis, was a sanitary nighmare, and not for the faint of heart.  Think "Deliverance," but in a river of sewage instead.  We wore gas masks, and brought several days worth of supplies just in case.  The cave is littered with soda straws and tampon applicators; quite what you'd expect, I suppose, for a cave under a nightclub.  Back in the 1980s the cave was reportedly swarming with cockroaches but they were inexplicably absent at the time of our visits.  Upon leaving the cave I was caught in sewer currents and nearly swept to the treatment plant!  The cave was discovered in 1904 by sewer workers and its formation may be related to a broken off artesian well.

ABOVE: A photo of "Little Minnehaha Falls," a ceiling spring.  Note the striped black and white, or "zebra," flowstone on the walls, deposited by groundwater.  BELOW: One of the two dozen pyramid-style concrete supporting piers holding up the city above.  Is this guy trying to push one of them out or what?