It would be interesting to know how the concept began, the belief that the underworld, Hell, if you will, is located underground. Was it because of volcanoes, spewing forth fire and brimstone? Then again, who decided that Hell was stuffed full of fire and brimstone, anyway? (Viking Hell is a place of agonizing COLD, for example.) The idea seems to be as old as human civilization: the underworld is under our collective feet. Taking that as a fact, it only makes sense that there would be passageways by which people could enter it without first having to die. Mythological heroes managed it all the time, though you have to wonder why anyone not on a heroic quest would want to go there. Doesn’t seem like it should be a popular vacation destination.
You can get to the realm of shadows—according to legend—via a system of caves in Greece, or by visiting the “City of Ghosts” in China, one can pass into Naraka, or Chinese Hell. The fiery pit of Hekla in Iceland is where the traitorous Judas Iscariot is imprisoned, according to a Medieval poem, and the souls of the damned are often seen circling its crater. There’s a doorway at the Roman Forum, and several located in certain cemeteries in New Orleans. (I missed ‘em the last time I was there! They weren’t on any of the tourism brochures!) A monastery sits on top of one in Ireland, and prisoners were once tortured in the “Bloody Hell Pond” of Japan—which is now part of a health resort! Hellam Township, Pennsylvania got its reputation as an entrance to the underworld due to the unfortunate spelling of its name. The creepiest, though, in this author’s not so humble opinion, is the Cave of the Crystal Sepulchre in Belize, which is reputedly an entrance to the Mayan Hell, Xibalba, where calcified skeletons of victims of human sacrifice still adorn its gloomy cathedrals. Plenty of ways to get to Hell, apparently. But are all those doorways marked “entrance only?”