As you go North on Interstate 75, take the Grayling exit and visit 'Michigan State of' (Hartwick Pines State Park), where you can see enormous Michigan white pines, including Michigan's tallest/largest tree, The General, along with a nicely-restored logging camp. This State park continues a stand of virgin (never harvested) pines, that are not only beautiful, but also incredibly old. The forest here is just permeated with an air of ancient serenity.

If you go further North, then head West to Beulah, to see 'Cherry Hut Restaurant', where you can get a good meal, a neat resort-type atmosphere, and the best cherry pie, cherry-ade, and cherry jams, preserves, jelly, and conserves in the world. Yum! (look for a dolphin, waving to you from nearby Crystal Lake)

Next, go back to I-75 and head North, over the Mackinac Bridge, and on up to Munising. Leave an entire day for 'Pictured Rocks Cruises Inc', plus there is wonderful camping, hiking, site-seeing (many little waterfalls), swimming (if you don't mind cold water), and kayaking. (look out over Munising Bay, for signs of a leaping dolphin)

Go back South, into the Garden Peninsula, to the Southern tip, to see 'Fayette State Park', with its nice museum and ghost-town. (the bay is excellent water for dolphins)

Finally, go North and West, to see 'Porcupine Mt Wilderness State Park', where there is wonderful hiking, rustic cabins, and the magnificent Lake of the Clouds. (no access for dolphins, sadly)