| 1. |  | Knife Blade Rock near Crystal Cave on B. H. & Ft. Pierre R'y, S. D., 175 feet high. | Crystal Cave (S.D.); Rock formations; | Exterior view of Knife Blade Rock, near Crystal Cave, S.D. Printed on front ends of mounting board: Black Hills, the Switzerland of America. Reached by the Northwestern Line. W. R. Cross, Photo, Hot Springs,... |
