It's about a two hour drive. I lived in Munising for several years so have a good knowledge of the area. There is a trail along the top of the Pictured Rocks (great views) but the Rocks are best seen from the water. Consider renting a kayak, or taking the boat cruise out of Munising. Also be aware that June is in the middle of "bug season" so if you do any hiking, you will be accompanied by hordes of mosquitoes, black flies and deer flies.
Originally Posted by mjs
Consider visiting or staying in Grand Marais, on Lake Superior, which is about 25 miles north of Seney. You'll have easy access to the Grand Sable dunes which are very impressive, especially in the evening as the low sun angle makes for dramatic shadows on the dunes. You can easily walk on the dunes too, and, because they're more exposed to the wind, no bugs.
Look on the Pictured Rocks National Lakeshore website for more info on the Rocks and the Dunes.