1930 : Detroit Windsor Tunnel Dedicated

November 1, 2021 all-day

Did you know that the Detroit-Windsor Tunnel is the only existing sub aqueous international automobile border crossing?

That means it is the only underwater-tunnel for automobiles that cross International borders in the entire world!

As you travel almost a mile, 75 feet below the surface of the Detroit River, you’re surrounded by 574 lights, 80,000 cubic yards of concrete, and 750 tons of reinforced steel.

The Tunnel has 4 acres of roadway area and one of the most elaborate ventilation systems ever devised.

Located between Detroit, Michigan and Windsor, Ontario, The Detroit Windsor Tunnel connects the U.S. Interstates to Ontario’s Highway 401. It is a large complex consisting of toll and inspection plazas on each side of the Windsor-Detroit border where you pay for your crossing and undergo inspections by Immigration and Customs.

The Tunnel provides one of the fastest links between Canada and the United States.

The tunnel has been recognized as one of the great engineering wonders of the world.

Other quick facts:

  • The Detroit-Windsor Tunnel was formally dedicated on Saturday, November 1, 1930. President Herbert Hoover turned a “golden key” in Washington that rang bells in both Detroit and Windsor to mark the opening of the tunnel.
  • The Tunnel first opened to traffic on November 3, 1930.
  • The Tunnel was finished a year ahead of schedule at a total cost of $23 Million.
  • The Tunnel is jointly owned by the Cities of Windsor, Ontario and Detroit, Michigan.
  • It is operated under two separate agreements by the Detroit and Canada Tunnel Corporation.
  • Approximately 12,000 vehicles pass through the Tunnel on a daily basis, handling over four million vehicles per year, of which 98% are cars, 2% are trucks and buses.
  • Ventilation – 1.5 million cubic feet of fresh air is pumped into the tunnel each minute.
  • Renovations: A $50 Million renovation program was launched in 1993, including a completely new road surface, new sidewall tiling, new lighting, complete video surveillance and restoration of the Tunnel’s stone cover beneath the Detroit River.


In 1871, ground was broken near the foot of St. Antoine Street for a tunnel under the Detroit River. It was to have a 15-foot bore, surrounded by masonry.

However, a pocket of sumptuous gas ended the project when workers were 135 feet out under the river. The gas made the workers so sick that none of them could be induced to resume work on the following day. The project was abandoned.

Detroit’s second tunnel venture took place in 1878, when a tube was proposed to connect Grosse Ile, Michigan with the Canadian mainland. No gas was encountered, yet this undertaking had to be abandoned because certain limestone formations made the cost of excavation prohibitive. In 1874, the Detroit Board of Trade made a determined effort to promote a bridge, despite the opposition of shipping interests. Nothing came of this project.

When the Grand Trunk Railway Tunnel under the St. Clair River at Port Huron opened in 1891, this caused another flurry of activity about additional tunnel construction. This railway tunnel was 6,000 feet in length and at the time was the longest, sub aqueous tunnel in the world. Detroit business interests, afraid of a diversion of shipping to Port Huron, made a desperate effort to generate public support for a tunnel in Detroit.

In 1906, construction began on the Michigan Central Railway Tunnel in Detroit and was completed four years later. It had a total length of two and one-half miles and cost $8,500,000. However, the opening of this tunnel did not lessen the agitation for vehicular transportation facilities across the Detroit River, especially after the phenomenal growth of the automobile industry. Bridge and tunnel advocates remained active in support of their respective undertakings, culminating several years later in an announcement that Detroit would have both projects.

In June 1919, Windsor’s Mayor Edward Blake Winter requested Ottawa to construct a tunnel as a memorial to soldiers who died in World War I. Winter’s argument was that a tunnel between England and France had been proposed as a war memorial, and if England and France could be united by a tunnel, so should Canada and the United States.

Despite the opinion of scientific experts that anyone using the tunnel would die of carbon monoxide poisoning, a Windsor Salvation Army Captain, Fred W. Martin, pursued the dream of a Detroit-Windsor tunnel. It was not until 1926, when a prestigious, New York architecture firm predicted that a tunnel would not only be feasible but profitable, that Martin found enough backing to get the project underway. A group of Detroit bankers agreed to back the project provided that the New York architects would design the tunnel and guarantee its construction costs.

Source : Detroit-Windsor Tunnel Web Site.