I think the OP would want Platte River CG. We go there several times each year and have even back 50 years ago when it was Platte River State Park CG. My nephew was a ranger there for many years and our whole large family would camp there every year. We were there again in the 1st week of May this year. One of our favorite CG's in the whole country. A very special place!
DH Day CG is dry camping and most of the sites are very small and many are unlevel as it's a nature CG and very old and dates back to the 1920's and was Michigan's very first state park. it's been preserved is a really neat CG for tenting or smaller RV dry camping abd has a great beach.
All sites in Platte River CG are paved for the RV and a vehicle. You must have all wheel on the pavement with no exceptions. A very beautiful large CG with really large sites and gorgeous tiled bathhouses 1 or 2 in each loop. Group camping area is away and beyond the RV area and there's a lot of "Walkin campsites" also beyond loop 4. Hiking trails everywhere! The very nice showers are on the rear of the bathouses with each having it's own private entrance door from the outside. It's a very large NP that stretches for many miles, like over 40, with so much to do and see. Very popular CG and gets very busy in summer and fall so is booked up all summer and most of the fall. The Platte River CG is open all year and the bathhouses and showers are heated and evey site in the open loops is alway plowed clear of snow as so many cross country ski or snowshoe in the winter or just camp etc.
Right now yet, some schools aren't out yet for the summer and you might be able to reserve a site.
Loops 1 3, and half of 4 are all reserve only. 4 doesn't have electric. Loop 2 is for drive ups only (non-reservable). Tokens are no longer used or needed for the showers as they are now included with the daily fee. Many sites are large enough for a 40' trailer and be sure to tell the length when reserving or registering. You must adhere to the CG's rules as they do not bend them and because there's lots of wildlife in the entire NP. Some of the sites have long wide paved area for the rv and tow vehicle and some are shorter but are double width as you park the tow vehicle along side the RV but closer to the CG road so you still have a patio. Lots of pamphlets and printed info in the checkin office for day trips. The entire area is simply gorgeous and why it's been rated several years as "The most beautiful National Park in the USA" and you'll se why!
You'll most likely go back many more times like about everyone else does. We know the CG manager and most of the employes as they have been there for so many years and are extremely helpful.
There's also lots of other private owned CG's in the area surrounding the NP so if you can't get a site in Platte, you can still get close and do daytimes in the NP as there's no entrance fee. A small fee for Dune Drive but so well worth it. No fee if you have a pass/disabled/etc and the CG is half price also as my wife is disabled and has the pass.
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