By Robert Earle Howells

Greenstone Ridge Trail

When: May to September

One-Way Trip: 40 Miles, 4 Days

Level: Moderate Backpacking Trip

This four-day, three-night hike traces the spine of the densely forested Lake Superior island that gives the least visited national park in the system its name. Whenever the trail breaks out of the woods—most impressively, atop 1,394-foot Mount Desor—you get a grand sense of remoteness while gazing down on the isle, dozens of surrounding barrier islands, and the sparkling lake. Even more thrilling is the chance for wildlife encounters—moose feeding in trailside swamps, loons in the many lakes, and the haunting howls of wolves at night.

Insider Tip: Hike from the southwest to the northeast. The Voyageur II ferry (www.isleroyaleboats.com) from Grand Portage, Minnesota, will drop you off at Windigo and pick you up at Rock Harbor, where there’s a small lodge (www.rockharborlodge.com).

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