It was constructed through Backbone Mountain[ii] during 1885–86, by the Fort Smith & Southern Railway (FSSR).

At the time it was built, the tunnel was located in the Choctaw Nation in Indian Territory.

[iv] The tunnel was created through Backbone Mountain in what is now Le Flore County, Oklahoma.

[1] One blogger reported that the tunnel was built on the east side of the Arkansas-Indian Territory border, but that a subsequent realignment of the border put it entirely inside the present state of Oklahoma.

[3] The tunnel was listed on the National Register of Historic Places (NRHP) on May 13, 1976.