If I remember right the from Elkhart County Fairgrounds in Goshen, Indiana take Highway 4 East to Highway 13, then go north on Highway 13 until you get to the Michigan boarder which then turns into US-131 follow that north, its all two lane until you get to three rivers then it's two lane divided highway until you get to Schoolcraft the it becomes a limited access highway. This route is used by many trailer manufactures to bring trailers North, you go through several towns going but the roads are good as we take that route going south as it cuts off well over 100 miles by taking I - 69 and I-94 to US-131. when you go north up to Cadillac it's all good roads, but as you approach Cadillac you will encounter a couple big hills and then a big downgrade going around Cadillac. I would suggest getting off at the Lake City and follow that east until you get to US-127 and then go North all the way to the bridge. From there the drive is very pleasant with lots of nice views and lots of tourist attractions. We camp up in the Grayling area at least 4 times a year as we love the atmosphere Don't know if tou use a GPS, but I would suggest yosing a road attlas as you will get a better idea of the route is just described. If you have any questions don't be afraid to ask. Hope this helps.
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