You can reserve Michigan state parks 6 months out from the dates you're trying to reserve. Website below.
https://www.midnrreservations.com/The west side of the state along Lake Michigan you will find that the state parks fill up very quickly, especially Ludington, Charles Mears SP, Holland, and Grand Haven. We often stay at Van Buren SP near South Haven and like it. We've also stayed at Orchard Beach SP near Manistee a couple of times. In the U.P. Brimley SP just west of Sault Ste Marie is very nice with grassy sites and a nice beach.
On the private side we've found Silver Creek RV Park to be especially nice with FHUs. It's near Hart, MI along Lake Michigan and near Silver Lake Sand Dunes. Website below.
http://www.silvercreekrv.com/Further north, west of Traverse City and near Sleeping Bear National Lakeshore is Indigo Bluffs (officially listed address is Empire). Most sites have water & electric. This area of the lower peninsula is by far my favorite and includes the Leelanau Peninsula (Glen Arbor-Leland-Suttons Bay & to a lesser extent, Traverse City). Website below.
http://www.indigobluffsrallypark.com/A municipal campground in the U.P. that we like, Woodland Park in Grand Marais. It's right on a bluff overlooking Lake Superior and the small village of Grand Marais is nice. You will be just east of Munising and Pictured Rocks National Lakeshore and can take a nice county road to Munising called H-58 or camp in Munising.
http://www.rvparkreviews.com/regions/Michigan/Grand_Marais.htmlIn the far western end of the U.P. is the Porcupine Mountains SP just south of Ontonagon. There is a state park there, but we prefer the township park on the north side of Ontonagon. The beach is nicer there and it has water & electric.
http://www.rvparkreviews.com/regions/Michigan/Ontonagon.htmlThere are a lot of nice campground all around the state, upper & lower. I prefer the Lake Michigan side with the beaches and dunes. Still, the Lake Huron side also has some nice campgrounds and of course the area around the Mackinac Bridge is a hot spot for tourists. Aloha SP, just south of Cheboygan is nice, but many people like the Mill Creek Campground, a private park just east of Mackinaw City.
Have a nice trip!
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