I always preplan, especially during the snowed in months.
This is just about my most used site,
Recreation.gov This is the COE reservation site.
Followed closely by https:
www.campgroundreviews.com
ALL US AND CANADA CAMPGROUNDS LOCATOR: STATE PARKS NATIONAL PARKS FORESTS MORE california oregon washington new york pennsylvania more
www.uscampgrounds.info
CampsitePhotos.com - Campsite Photos and Camping Information is a good one, but does have limited listings.
And here are some more that I do frequent on occasions:
The only campground and RV park search engine with virtual tours, videos, photos and the information that helps pick better campsites.
www.campgroundviews.com
RV Parky | RV Parks & Campgrounds Directory, Reviews, Photos, is more for commercial or private campgrounds
Another decent search site is
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This is about the best site for info on a given park, but the listings are limited,
Toad Hall. He does a stellar job on photos.
This is also valuable info,
A Guide to State Park Entrance Passes in All 50 States Show admission/use fees & discounts if available.
An amusing site is
Roadside America - Guide to Uniquely Odd Tourist Attractions.
Allstays.com, has decent info to offer.
This has some interesting info but is a bit awkward to navigate.,