Mackinac Straits Auto Tunnel
Sector: Road • Location: Michigan, United States
Source: NewsBreak: Local News & Alerts
A proposed tunnel under the Straits of Mackinac to replace or supplement the Mackinac Bridge, allowing vehicle traffic to pass beneath the straits. The tunnel would be approximately 5 miles long, making it the longest tunnel in the United States if constructed. The idea is inspired by the existing Great Lakes Tunnel Project for a pipeline under the straits.
- Status
- Prospective
- Sector
- Road, Bridge, Tunnel
- Location
- Michigan, United States of America
- Updated
- 22 Jul 2026
- Source
- NewsBreak: Local News & Alerts
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Project Information
Participants
| Not available for this record. |
Status
Original status | proposed |
Taiyo status | Prospective |
Taiyo last update | 2026-07-22 |
Contact
| Not available for this record. |
Description
Description | A proposed tunnel under the Straits of Mackinac to replace or supplement the Mackinac Bridge, allowing vehicle traffic to pass beneath the straits. The tunnel would be approximately 5 miles long, making it the longest tunnel in the United States if constructed. The idea is inspired by the existing Great Lakes Tunnel Project for a pipeline under the straits. |
Original sector | Transportation |
Location
Country | United States of America (USA) |
State | Michigan |
Source
Source | NewsBreak: Local News & Alerts |
URL |
More Details
Record type | Project |
Sector | Road, Bridge, Tunnel |
Article published date | 2025-09-16 |
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