The Worm’s Hole is what fishermen call a "blowhole" or a shoreline window to subterranean caverns, which spurt out water each day as high tide approaches. What significantly differs about the Worm’s Hole from other blowholes, though, is that it’s a near-perfect rectangle, thus its culturally inexplicable nature. And to fully understand the extraordinary characteristics of this stunning natural wonder, which is as visually moving as any towering waterfall or raging river, one should review some background on the Aran’s geological and mythological make-up.