Travel to Old Faithful Geyser

Yellowstone National Park's famous geyser Old Faithful has been called the most predictable geographical feature in the world. Its reliability has been documented since 1870, when Minnesotan explorer Nathaniel P. Langford gave it its now-world-famous moniker. The eruptions come in two flavors: if an eruption lasts less than 2.5 minutes, the next one will be in 65 minutes. If an eruption lasts more than 2.5 minutes, the next one will be in 91 minutes.