The story
In 1900 prospectors Frank and Albert Michaud felt cold air blowing from a hole, enlarged it, and found a cavern lined with sparkling calcite crystals — Jewel Cave. Theodore Roosevelt proclaimed it a national monument on February 7, 1908, the first ever established specifically to protect a cave. By 1959 less than 2 miles were mapped; then cavers Herb and Jan Conn pushed it past 64 miles by 1979. As of mid-2025, over 220 miles are mapped, making it the second-longest cave in the U.S. — and experts think that's under 5% of its true extent.
Everything that was here
- 1900–present · still open
Jewel Cave National MonumentNational Monument
Two prospector brothers chasing cold air out of a canyon crack in 1900 found what has since grown, mile by surveyed mile, into one of the longest caves on Earth.
See the map in 1901 →
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Connected places
St. Louis Coliseum
Hyperion Theater
Temple of Music (Pan-American Exposition)
Hotel Schenley (William Pitt Union)
Black Cat Cafe
Explore the full web of connections on the map.
Nearby history
Flintstones Bedrock City
Custer City
1874 French Creek Gold Discovery Site
Crazy Horse Memorial
Gordon Stockade
Sylvan Lake
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