One of the most famous geysers in the nation, Old Faithful got its name because of its predictability. Perhaps this is the reason why this geothermal eruption is so famous - people know they'll get a show as long as they wait about an hour to an hour and a half. Old Faithful's steamy eruptions, which reach a height of about 106 to 185 feet, last from 2 to 5 minutes. When it was first discovered in 1870, it was used as a laundromat. It wouldn't be advisable to use it as such nowadays; doing so might get you escorted out of Yellowstone.