An Underground Junction in a side tunnel from the Article SOME IMPORTANT MINING TUNNELS IN COLORADO. By TJiomas Tonge. from The Engineering Magazine DEVOTED TO INDUSTRIAL PROGRESS Volume XII October 1896 to March 1897 The Engineering Magazine Co

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Size: 1679px × 1960px
Location: Colorado, USA
Photo credit: © Historic Illustrations / Alamy / Afripics
License: Royalty Free
Model Released: No

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