These maps are very detailed, but be aware that some roads shown are not suitable for all vehicles. Information included in these maps include topographical maps, parks, campgrounds, rivers, lakes, wildlife areas, trails, fishing areas, boat launch areas and much more.
US Forest Service - USFS - Describes USFS policies and rules about RV camping. Information about dispersed camping, and tips on how to find great free RV camping sites.
National Park Service (NPS) - General information about RV camping and campgrounds in US National Parks. With campgrounds in the most historic and scenic places in the country, the NPS offers some of the best places for RV camping.
US Army Corp of Engineers (USACE/COE ) - USACE (perhaps better know as COE) manages water recreation areas throughout the USA. Information about finding USACE lakes, RV camping possibilities, and rules and policies for use of these water based recreation areas is included.