Interior view of Detroit River Tunnel along railroad track. Printed on front: "Interior of the Detroit River Tunnel, Detroit, Mich." Printed on back: "Interior of Detroit River Tunnel, Detroit, Mich. The Detroit River Tunnel was built for the M.C.R.R. at a cost of $8,500,000. It is 1 3/8 miles in length. Construction was started in July 1906 and completed July 1, 1910. Electricity, the third rail system, furnishes the motive power for the engines. C.T. Co., Chicago, A-17409."
