Old Faithful is a cone geyser in Yellowstone National Park in Wyoming. It was named in 1870 during the Washburn–Langford–Doane Expedition and was the first geyser in the park to be named. It is a highly predictable geothermal feature and has erupted every 44 minutes to two hours since 2000. Let everyone know you are a fan of the centerpiece of the Old Faithful Historic District when you wear this Old Faithful Yellowstone National Park T-Shirt!