About every 30 minutes, visitors to the Old Faithful Geyser of California are treated to an eruption of steam and scalding water spraying 60 to 100 feet in the air. There are only two other "old faithful" geysers in the world that have earned the title due to their regular eruptions. This geyser has also proven itself to be a good predictor of earthquakes. When the geyser's show is delayed or diminished, an earthquake is likely within the next couple of weeks in the 500 miles surrounding the geyser