how tall is old faithful
Even so, it is worth waiting to see. Grand erupts from a pool of water making it a fountain-type geyser as opposed to Old Faithful which is a cone-type geyser. Grandâs interval is usually around 8-12 hours, its height about 150-180 feet and its duration is about 10-12 minutes. It will often stop after about 9 minutes and then restart after a minute or so.