Valles Caldera, New Mexico. Lots of forest service roads, really pretty area. Maybe north rim Grand Canyon. Theres a trail along the rim, perfect for that bike. Bicycle Touring Pro did a trip and video here, looked lovely
Or
Vermont. Tons of gravel roads, a lot of National Forest so you can camp in a lot pf places. Vermont State Parks are also many, pretty and well sited. Theres a thread here.
https://www.bikeforums.net/touring/1...ip-report.html
Also West Virginia, same reasons, tons of gravel roads, all in National Forests, so lots of camping opportunities
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