In 1920, Robert Limbert, a Boise taxidermist, trekked across 28 miles of lava flows and then convinced Congress to include the lava fields in the national park system. In 1924, President Coolidge declared 83 square miles as a National Monument. Congress established the Craters of the Moon Wilderness in 1970. Today, more than 250,000 visitor from around the world visit the reserve to see strange rock formations and explore a series of underground caves. Wildflowers of many species bloom every spring in this barren land.