.jpg) 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)[2] |
| 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[1] |
| Focal height | 130 feet (40 m)[3] |
| Lens | 2nd Order bivalve Fresnel Lens[5][6] (original), 12-inch (300 mm) Tideland Signal ML-300 Acrylic Optic[7] (current) |
| Range | 15 nautical miles; 27 kilometres (17 mi)[4] |
| Characteristic | two flashes every 10 s[4] |
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[8] |
| 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))[9] 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.[10][11]
- ^ "Historic Light Station Information and Photography: Michigan". United States Coast Guard Historian's Office. Archived from the original on 2017-05-01.
- ^ Pepper, Terry. "Database of Tower Heights". Seeing the Light. terrypepper.com. Archived from the original on 2000-09-18.
- ^ Pepper, Terry. "Database of Focal Heights". Seeing the Light. terrypepper.com. Archived from the original on 2008-08-30.
- ^ a b Light List, Volume VII, Great Lakes (PDF). Light List. United States Coast Guard.
- ^ Pepper, Terry. "Database of Original Lenses". Seeing the Light. terrypepper.com. Archived from the original on 2000-09-18.
- ^ In 1908, a 3rd Order Fresnel lens was temporarily installed, but the lantern was designed for the 2nd Order lens, which had not yet arrived. Wobser, David, "Rock of Ages Light" Great Laker magazine (December, 2004) Archived 2008-07-20 at the Wayback Machine, Boatnerd.com
- ^ Terry Pepper, Seeing the Light, Rock of Ages Light.
- ^ "National Register Information System". National Register of Historic Places. National Park Service. March 13, 2009.
- ^ Roach, Jerry (2007). "Rock of Ages light" The Ultimate Guide to Upper Michigan Lighthouses. Bugs Publishing LLC. ISBN 978-0-9747977-2-4. Retrieved 16 January 2011.
- ^ "Rock of Ages (Lake Superior) Light ARLHS USA-698". Amateur Radio Lighthouse Society. Retrieved January 6, 2013.
- ^ "World List of Lights". Amateur Radio Lighthouse Society. Retrieved January 6, 2013.