The Detroit–Windsor Tunnel is 5,135 feet long, equal to about 0.97 mile or 1.57 kilometers.
A driver asking how long the Windsor Tunnel is needs one practical number: the road runs 5,135 feet from the Windsor portal to the Detroit portal. That makes the international crossing 145 feet short of a full mile.
The name commonly refers to the Detroit–Windsor Tunnel beneath the Detroit River, linking downtown Windsor, Ontario, with downtown Detroit, Michigan. The tunnel itself takes only a few minutes to drive when traffic is moving, but customs inspection and border queues can make the complete crossing much longer.
Windsor Tunnel Length In Miles And Kilometers
The Windsor Tunnel measures about 0.973 mile, 1.565 kilometers, or 1,565 meters from portal to portal. For everyday trip planning, describing it as “just under one mile long” is accurate.
A full statute mile contains 5,280 feet. Subtracting the tunnel’s official 5,135-foot measurement leaves a difference of 145 feet, or about 44 meters. That is roughly half the length of an American football field when its end zones are included.
The figure covers the crossing between the entrance portals, not the approach streets, toll plaza, inspection booths, or connecting roads. A vehicle travels farther than 5,135 feet when the full border-crossing process is counted.
Why Published Lengths Differ Slightly
Published descriptions usually list the Detroit–Windsor Tunnel as either 5,135 feet or 5,160 feet long. The official operator currently gives 5,135 feet from the Windsor portal to the Detroit portal, while some engineering and historical references use the slightly longer figure.
The two measurements differ by only 25 feet, equal to about 7.6 meters. That small gap can result from different choices about where a structure begins and ends, such as whether short portal sections are included.
Useful figure: Use 5,135 feet for the current portal-to-portal measurement and “nearly one mile” for a simple description.
Detroit–Windsor Tunnel Facts At A Glance
The tunnel’s length is only one part of its unusual design. The crossing carries road traffic beneath a river and across the international boundary between Canada and the United States.
| Tunnel Detail | Figure | What It Means |
|---|---|---|
| Portal-to-portal length | 5,135 feet | The operator’s current stated measurement |
| Length in miles | About 0.973 mile | Nearly one full statute mile |
| Length in kilometers | About 1.565 kilometers | Approximately 1.57 kilometers when rounded |
| Distance short of one mile | 145 feet | About 44 meters less than a mile |
| Maximum roadway depth | About 75 feet below the river surface | The roadway descends beneath the Detroit River |
| Traffic lanes | Two lanes | One lane normally carries traffic in each direction |
| Opening year | 1930 | The crossing has operated for more than nine decades |
| Connected downtowns | Detroit and Windsor | The portals sit close to both city centers |
| Reported daily traffic | About 12,000 vehicles | Most users travel in passenger vehicles |
The official Detroit–Windsor Tunnel description states that the crossing extends 5,135 feet between its two portals. The same source reports roughly 12,000 vehicles per day and more than four million vehicles per year.
How Long Does It Take To Drive Through?
The moving portion of a drive through the Detroit–Windsor Tunnel normally takes only a few minutes. Total crossing time depends far more on traffic, toll processing, customs inspection, lane availability, and the documents carried by each traveler.
A clear tunnel does not guarantee a fast border crossing. Vehicles must approach the plaza, pass the toll point, drive through the tunnel, and complete inspection after reaching the other country. Busy weekends, sporting events, holidays, and commuter periods can add time before or after the mile-long tunnel section.
Travelers should separate two different time estimates:
- Tunnel driving time: The brief period spent moving between the two portals.
- Border crossing time: The full period from joining the approach traffic to leaving customs.
- Downtown travel time: The additional drive between the crossing and the traveler’s actual destination.
Checking current traffic conditions before departure gives a more useful estimate than calculating travel time from the tunnel’s length alone.
Is The Windsor Tunnel Underwater?
The Detroit–Windsor Tunnel passes beneath the Detroit River, with its roadway reaching about 75 feet below the water’s surface at the deepest point. The structure rests in a prepared trench near the riverbed rather than floating in the water.
The underwater portion was assembled from nine large steel tube sections. Builders constructed the tubes on land, moved them into position, lowered them into a dredged trench, joined them, and covered the completed structure with protective material.
The tunnel also contains ventilation spaces separate from the road deck. Large fans move fresh air through the structure and remove vehicle exhaust, allowing a two-lane road to operate inside an enclosed tube almost one mile long.
What The Length Means For Drivers
The 5,135-foot length makes the tunnel a compact downtown-to-downtown border route rather than a long underground highway. Drivers enter near central Detroit or Windsor and emerge in the other country after traveling less than one mile inside the structure.
The short distance does not remove international-entry requirements. Every traveler must carry documents accepted for the direction of travel, and customs officers may ask questions or direct a vehicle to secondary inspection. Vehicle restrictions also matter because the enclosed roadway has less clearance and maneuvering space than an open bridge.
Drivers can prepare for the crossing by doing three things:
- Check the current traffic report and any scheduled tunnel closures.
- Confirm that every passenger has the correct border document.
- Verify vehicle size and cargo restrictions before entering the approach lanes.
The physical drive is simple once a vehicle reaches the portal. Most uncertainty comes from border conditions, not from the distance beneath the river.
The Measurement To Use
The clearest answer is 5,135 feet from portal to portal, which equals about 0.97 mile or 1.57 kilometers. Describing the Detroit–Windsor Tunnel as nearly one mile long is both easy to understand and consistent with the operator’s current measurement.
The occasional 5,160-foot figure is only 25 feet longer and does not change the practical answer. For trip planning, expect a drive of a few minutes inside the tunnel and allow separate time for tolls, traffic, and customs inspection.
References & Sources
- Detroit Windsor Tunnel LLC.“About the Detroit Windsor Tunnel.”Provides the portal-to-portal length and current operating statistics for the crossing.