Soda Butte Creek is an approximately 20 miles long major tributary of the Lamar River in Yellowstone National Park. It is named for a now-extinct geyser (Soda Butte) near its mouth. Soda Butte and the creek were named by A. Bart Henderson, a Cooke City miner, in 1870. It rises just outside the northeast corner of the park on the southern slopes of the Absaroka …Soda Butte Creek is an approximately 20 miles long major tributary of the Lamar River in Yellowstone National Park. It is named for a now-extinct geyser (Soda Butte) near its mouth. Soda Butte and the creek were named by A. Bart Henderson, a Cooke City miner, in 1870. It rises just outside the northeast corner of the park on the southern slopes of the Absaroka Range near Cooke City, Montana. The Northeast East Entrance road parallels Soda Butte Creek for its entire length within the park. Soda Butte Creek is a popular angling destination for native Yellowstone cutthroat trout.