Drag to compare unlit and lighted · live NOAA chart, not for navigation
Mackinac Island & the Mackinac Bridge
Straits of Mackinac
Where Lake Michigan meets Lake Huron, in one long panorama under the bridge.
The Straits join two Great Lakes beneath the five-mile Mackinac Bridge. Round Island's old lighthouse counts out its paired flashes off Mackinac Island, and the harbors of St. Ignace and Mackinaw City light the shores on either side.
Signature lightOld Round Island Point LightFl (2) 10s 53ftTwo white flashes in a row, repeating every 10 seconds
- Frame
- 36 × 12 in
- Print scale
- 1 : 39,400
- Navigation aids
- 55
- Lights
- 38
38 lights glow on the finished chart, each through a pinhole fed by its own LED. The other 17 markers, such as daybeacons and unlit buoys, are printed on the chart.
5 light rhythms on this chart
- Flashing
- Group flashing
- Quick
- Occulting
- Fixed
Lights on this chart
- Round Island Passage LightOne red flash every 5 secondsFl R 5s 71ft 9.6M
- Saint Helena LightOne white flash every 6 secondsFl 6s 71ft 5.2M
- Mackinac Island East Breakwater Light 2One red flash every 2.5 secondsFl R 2.5s 25ft 4.3M
- Mackinaw City Harbor Entrance Light 1One green flash every 2.5 secondsFl G 2.5s 25ft 4.3M
- Mackinac Island West Breakwater Light 1One green flash every 2.5 secondsFl G 2.5s 33ft 3.5M
- Mackinaw City Harbor Entrance Light 2One red flash every 4 secondsFl R 4s 25ft 3.5M
Opens in the designer, ready to adjust the area, frame and title. Starting at $299, based on frame size, LED configuration and custom programming. Data current to November 5, 2026.