Witness the power of Old Faithful and explore the surrounding geyser basin with this self-guided walking tour! As one of the most densely-packed geyser regions in the park, there’s no shortage of explosive wonders on display here. Watch huge geysers like Old Faithful, Castle Geyser, and Grand Geyser erupt. Stroll past smaller, bubbling pools. Find out how geysers form and work, and uncover the hidden systems underlying the whole basin. This walking tour makes for the perfect addition to any Yellowstone visit! After booking, check your email to download the separate Audio Tour Guide App by Action, enter your unique password, and access your tour. These steps require good internet/Wi-Fi access. From there, follow the audio instructions and the route. New, extra validity — now yours for an entire year! Use multiple times over multiple trips! This isn't an entrance ticket. Check opening hours before your visit.