Mount Desor is the highest point on Isle Royale National Park, the most remote and least visited National Park outside of Alaska. It can only be reached by ferry (or, if you have money to burn, floatplane). The peak is an 8.5 mile hike from the nearest ferry landing, so there is pretty much no way to avoid a multi-day expedition. Sadly, Desor is not a county high point (the island is part of Keweenaw County, which has its HP on the mainland), nor is it the highest point in Lake Superior (two islands in Canada have higher peaks). But it is still a worthwhile wilderness trip for the “parkpointer” trying to bag the National Park summits.
These notes are meant for the minority of Isle Royale visitors that have Mount Desor as their main goal.
Conveniently for the highpointer, Mount Desor lies relatively close to the Windigo ranger station, where the shortest ferry route to the island leaves off hikers. This ferry, a two-hour trip from Grand Portage, Minnesota, runs from May to October and it is essential to get reservations in advance. There are two boats on this run (The Voyageur II, which circles the island three times a week; and the Wenonah, making trips every day) and you should check the web site at http://www.grand-isle-royale.com for the latest schedule and fare information.
Most visitors to the Isle Royale backcountry hike the length of the island for several days, and climbing Mount Desor could easily be part of a trip like this along the 45-mile Greenstone Ridge Trail. However, if all you want is the highpoint and a quick introduction to the island, you can spend just one night by following the following itinerary:
Get your tent, sleeping bag, and other overnight gear into a pack, and ride the 8 AM ferry from Grand Portage to Windigo, arriving on the island at 10 AM. At the dock, you must go through a mandatory ranger orientation and register for your campsites. Tell them you will just spend one night, at the Island Mine campsite. You should be able to be on the trail by 11 AM. Hike the Greenstone Ridge Trail northeastwards for 6.2 miles, over the indistinct hump of Sugar Mountain, to a trail junction.
Mount Desor is ahead, but you should probably first set up camp by turning right for a 0.4 mile up-and-down hike to the Island Mine campsite, where there are 4 individual tent sites and 4 group sites in the forest.
After you set up your tent, return to the Greenstone Ridge Trail and continue northeast another 2.3 miles to Mount Desor. This is just a spot in the dense forest and not a well-defined summit, but when I was there in 2006 it was pretty easy to tell when you reached it. There was a small cairn to the right (southeast) of the trail on the high ground, and careful map reading will tell you when you are close—no need for a GPS. There is a pretty steep descent if you go too far. If you are coming from the northeast, then the cairn will be to your left, after the steep climb. If it is late September or later, you may see a very limited view to Sinewit Bay though the trees to the south.
Retrace your steps to the junction and then your campsite, where you can enjoy a night on a wilderness island and may hear the sounds of wolves howling in the distance.
The next morning, retrace the 6.6 miles to Windigo in time for the 12:30 PM ferry to Grand Portage—this will take most hikers three hours or less. All the hiking on this trip is on well maintained trails with easy terrain—hikers used to the Appalachians or Rockies will have no trouble at all. The total elevation gain on the hike is probably less than 1000 feet.
Bring insect repellent or head nets if you go before August. If you are just spending the one night, it makes sense to bring all the water you need with you, since the water at Island Mine is questionable (tapeworms!) and you will likely not need much in the generally cool forest with little elevation gain. The island may be a bit crowded in July-August, but you can’t reserve campsites in advance, so if Island Mine is full talk to the ranger for other options.