Sawmill Geyser, Yellowstone National Park Postcard

"Sawmill Geyser, Upper Geyser Basin, Yellowstone National Park, Wyoming" by Catherine Sherman Sawmill Geyser erupts in a barren landscape, surrounded by sparse greenery and an evergreen forest. Old Faithful Inn is in the background. Fluffy clouds float in the bright blue sky. Sawmill Geyser, named for the whirring sound it makes during its eruption, is a geyser in the Upper Geyser Basin of Yellowstone National Park, Wyoming, United States. The geyser was named by Antoine Schoenborn of the Hayden Geological Survey of 1871. Sawmill was a frequent eruptor in recent years prior to January or February 2017. It stopped erupting for four years, and then resumed eruptions on June 24, 2021. The geyser has an irregular pattern of eruption due to the underground structural interconnectivity which is characteristic of geyser complexes. Despite this, it tends to have a delay around 1 to 3 hours between eruptions. Sixty percent of the world's geysers are in Yellowstone National Park. The geysers of the Upper Basin in Yellowstone National Park represent the most concentrated group in the world - more than 250 are found in an area just two miles across. The majority of those are in a narrow band along both sides the Firehole River. There are five distinct geyser groups, beginning in the south at Old Faithful and nearby Geyser Hill. Two more groups are at Black Sand Basin, alongside Iron Spring Creek, and Biscuit Basin in the north, which is also along the Firehole River but more separated from the main region. The Old Faithful Inn was built during the winter of 1903–1904. The Old Faithful Inn is one of the few remaining log hotels in the United States. Wings were added to the hotel in 1915 and 1927, and today there are 327 rooms available to guests in this National Historic Landmark. This photograph was taken on September 9, 2022.