Old Faithful Geyser of California. In the early days of the National Geographic Society, Old Faithful Geyser of California was declared one of only three “faithful” geysers in the world because of its regular eruptions. This geyser has also proven itself to be a good predictor of earthquakes. When the geyser’s regular eruptions are delayed or diminished, an earthquake is likely within the next couple of weeks in the 500 miles surrounding the geyser. Old Faithful Geyser of California soon became one of the most visited places in the American West. The rainbows that form in the predictable sprays of mist are a wonderful feature in this serene setting at the top of Napa Valley. To this day, Old Faithful Geyser of California remains as one of the most photographed places in the State of California.

In a world of modern plumbing, it's hell being a geyser. Travelers of past centuries stood and watched, agog, as heated water blasted heavenward from rocky fissures. It was a true mystery. Today you get the same effect from a broken fire hydrant or the fountain show at the Bellagio. With a geyser, it's important to keep in mind that the phenomenon is not manipulated by Man: it's an underground river encountering hot magma deep in the earth and squirting for its own amusement -- not your vacation convenience. Three geothermal geysers in the world are predictable, erupting as if set on clocks, and are called Old Faithfuls.