Rock of Ages Light
Undated United States Coast Guard photo | |
| Location | Isle Royale, Michigan |
|---|---|
| Coordinates | 47°52′00″N 89°18′48″W / 47.86667°N 89.31333°W |
| Tower | |
| Constructed | 1908 |
| Foundation | Concrete Pier Steel Caisson |
| Construction | Steel, Masonry, Concrete |
| Automated | 1978 |
| Height | 117 feet (36 m) |
| Shape | Cylindrical base/Frustum of a Cone tower |
| Markings | White Black base and lantern |
| Heritage | National Register of Historic Places listed place |
| Light | |
| First lit | 1910 |
| Focal height | 130 feet (40 m) |
| Lens | 2nd Order bivalve Fresnel Lens (original), 12-inch (300 mm) Tideland Signal ML-300 Acrylic Optic (current) |
| Range | 15 nautical miles; 27 kilometres (17 mi) |
| Characteristic | two flashes every 10 s |
Rock of Ages Light Station | |
| Nearest city | Grand Portage, Minnesota |
| Area | 0.1 acres (0.040 ha) |
| Architect | Keller; Beger, Walter F. |
| MPS | U.S. Coast Guard Lighthouses and Light Stations on the Great Lakes TR |
| NRHP reference No. | 83000881 |
| Added to NRHP | August 04, 1983 |
The Rock of Ages Light is a U.S. Coast Guard lighthouse on a small rock outcropping (50 by 200 feet (15 m × 61 m)) approximately 2.25 miles (3.62 km) west of Washington Island and 3.5 miles (5.6 km) west of Isle Royale, in Eagle Harbor Township, Keweenaw County, Michigan (see map below). It is an active aid to navigation.