Documents Man-Made Caves of Salt

Man-Made Caves of Salt An enormous salt mine has been operating beneath Detroit for more than a century. Click here to see a drawing of an 1896 mine operation. This bed of…

Documents Man-Made Caves of Salt An enormous salt mine has been operating beneath Detroit for more than a...

Man-Made Caves of Salt An enormous salt mine has been operating beneath Detroit for more than a century. Click here to see a drawing of an 1896 mine operation. This bed of…