Coming across the U.P you would probably be best served to take US 2 across. It is the southern route and offers a great ride with rolling hills and breathtaking scenery from Ironwood to Iron Mountain and Lake Michigan on your right side from Escanaba all the way to the straits of Mackinac. There are some neat things to see on the northern route, State Highway M-28. The National Ski Hall of Fame in Ishpeming, Seney National Wildlife Refuge, The Pictured Rocks National Lakeshore in Munising, Grand Marais (It's an old logging port on the shores of Lake Superior) the town of Paradise (another old logging town turned tourist trap), which is near the Great Lakes Shipwreck Museum. It has the bell of the famous shipwreck made famous by Gordon Lightfoot, the Edmond Fitzgerald. If you take the north route, you will miss perhaps the highlight of the entire trip, the Mackinac Bridge which you would have to take I-75 south for 30 miles then back track to the Soo. The problem with most of these tourist attractions is that you will have to drive off M-28 anywhere from 10 to 45 miles one way to get to the site. If time isn't a problem, then I suggest the Northern route. Either way you choose, you will be in for some great scenery. If you need particulars, let me know. I've lived in the UP my entire life and have traveled both routes quite a few times.