It’s a popular hiking spot now, but in the late 1800s and early 1900s, it was an important way for Colorado mining businesses ...

This article was originally published with the title “ Ancient Salt Mines of the Indians ” in Scientific American Magazine Vol. 135 No. 2 (August 1926), p. 116 doi:10.1038 ...

Hall was a rich salt-mining center when Innsbruck was just a humble bridge (Brücke) town on the Inn River. Sprawling Innsbruck’s tourist industry crowds into its tiny medieval town center.