Rock of Ages Light
By Dave Wobser

This article originally appeared in Great Laker magazine in the December 2004 issue.

When lighthouse enthusiasts think of Isle Royale, the usual thoughts are of a remote island in the middle of Lake Superior, and light stations that most of us can only see in picture books. The 45 mile long, by 8 mile wide, island lies only 14 miles off the Canadian shore near the Minnesota-Canada border. By boat, the island is 22 miles from Grand Portage, Minnesota and 73 from Houghton/Hancock, Michigan, yet only about 17,000 visitors come to this National Park Service island each year.

Isle Royale area has a long history related to the mining and shipping industries that goes back as early as the 1800ís when several fishermen set up camps on the island. Then in 1837 John Jacob Astorís American Fur Company established a trading post to do business with the Native North Americans. The island was opened to mining exploration in 1843 and more than a dozen copper companies had a presence on the island within four or five years.

However, the majority of the copper mining activity was first centered on the Keweenaw Peninsula. Michigan State geologist Douglas Houghton reported a large boulder of pure copper and this started a rush to the Keweenaw by miners and speculators. Beginning in 1848, light stations were established at Copper Harbor, Whitefish Point, Manitou Island, Eagle Harbor, Ontonagon, and Eagle River, over a period of just four years.

Congressional authorization, in 1852, for the building of a lock at the Soo increased the interest in Lake Superior shipping and lobbying began for a light at Rock Harbor. Rock Harbor was closed for the last time in October, 1879.

Part of the demise of the Rock Harbor Light station was caused by the establishment of the Isle Royale Light on tiny Menagerie Island off the southeast shore of Isle Royale in 1875.

The third light station to be erected in the Isle Royale area was on the south end of Passage Island, which lies some three and one-half miles off the northeast end of the big island. The station was completed enough for the light to be shown on July 1, 1882.

Rock of Ages Light was made necessary by the growth of the Port of Duluth and the desire of vessel captains to travel along Lake Superiorís north shore in order to avoid storms and uncertain weather conditions in the western end of the lake. Lying a little more than two miles off the western end of Isle Royale, the small strip of Rock of Ages rose less than 20 feet above the water, and was in the path between the end of the Keweenaw Peninsula and the north shore.

As early as 1896 the Lighthouse Board requested funds for a light on this small rock, but it was not until 1906 that funds were made available. Designed with the state-of-the-art steel skeleton, work began on the structure in 1908. The concrete caisson that forms the first level is 25 feet high and contains a two-story cellar. A central steel core runs from the bedrock up through the center of the structure and provides that main support.

A total of six above-water decks provide space for fog signal equipment, office and common room, mess room, kitchen, and sleeping quarters on the fourth and fifth levels. The sixth level is the service room and the lantern is the seventh level. The housing was a lot like living in an elevator shaft. John Tregumbo served one season at Rock of Ages in 1947 as part of the three-man crew. As an 18-year old USCG rookie, Tregumbo thought "I must have really made someone unhappy to get this assignment".

A temporary Third Order Fresnel lens was installed and put in service late in the 1908 season. The station had been designed to house a Second Order Fresnel, which indicates the importance that was placed on the light. However, due to a lack of funds the Second Order Lens was not purchased and installed until 1910. The magnificent lens was removed in 1985 and is now prominently displayed in the Windigo Visitor Center on Isle Royale.

The up-close view of the lens is worth the trip to the island all by itself. The display stands over ten feet tall including the original clockworks. It is a clam-shell design similar to Split Rock. The Rock of Ages lens differs from a similar lens at Split Rock in that it has a double bulls-eye on each side. The light would have provide a flash-flash, pause, flash-flash pattern when rotating, whereas Split Rock had a flash, pause, flash pattern.

Getting there, some pundit once said is half the fun. In the case of Isle Royale the lighthouse photographer has several choices. None of them are a perfect answer.

Rock Harbor Light is the only lighthouse actually located on Isle Royale, but you cannot walk to it. The National Park Service maintains a nice museum in the light station and you can climb the tower. If you stay at the Rock Harbor Lodge, the lodge offers boat trips to Rock Harbor Light ,the nearby Edison Fishery and to Passage Island, aboard the M/V Sandy.

Two passenger vessels, M/V Voyageur II and M/V Wenonah, make the trip from Grand Portage, Minnesota to Windigo Harbor. The Wenonah offers day trips to Windigo Harbor that pass by the Rock of Ages light. The Voyageur II makes trips to Windigo Harbor and Rock Harbor, but requires an overnight stay on the island. For more information about either of these vessels, write to Grand Portage-Isle Royale Transportation Line Inc., 1507 N. First Street, Superior, WI, 54880, or on-line at their website.

The Isle Royale Queen runs to the island out of Copper Harbor, Michigan, and the National Park service operates the Ranger III out of Hancock-Houghton, Michigan. These vessels are geared toward the backpacker, camper, kayaker crowd and do not offer much for lighthouse enthusiasts.

In 2004, the Great Lakes Lighthouse Keepers Association ran a special two-day trip aboard the Keweenaw Star out of Houghton. The cruise was designed for lighthouse photography, and provided close-up views of all four Isle Royale lighthouses. There is a possibility this trip will be repeated in the future, by the Keweenaw Star, so more lighthouse fans will have a chance to see these remote stations.

To learn more about Isle Royale National Park, write to 800 East Lakeshore Drive, Houghton, MI 49931-1895, or on the web

Click on image to enlarge

Photographs by Dave Wobser

Location: On a small rock lying about two miles off the south end of Isle Royale.
Date Built: 1908
Active: Yes

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