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For those with low-bandwidth:
Free Camp Sites Website: https://freecampsites.net/ Andriod App: https://play.google.com/store/apps/details?id=net.freecampsites.androidapp
Campendium Website: https://www.campendium.com/ IPhone App: https://itunes.apple.com/us/app/campendium-rv-tent-camping/id1191380095
Travel Roads Website: https://apps.fs.fed.us/TravelAccess/
Crown Lands (Canada - Ontario) Website: https://www.ontario.ca/page/crown-land
Hiking - AllTrails Website: https://www.alltrails.com/ Android App: https://play.google.com/store/apps/details?id=com.alltrails.alltrails iPhone App: https://itunes.apple.com/us/app/alltrails-hiking-mountain/id405075943
IOverlander Website: http://ioverlander.com/ Andriod App: https://play.google.com/store/apps/details?id=com.samchristiansen.ioverlander.droid iPhone App: https://itunes.apple.com/us/app/alltrails-hiking-mountain/id405075943
Gas Buddy Website: https://www.gasbuddy.com/ Andriod App: https://play.google.com/store/apps/details?id=gbis.gbandroid iPhone App: https://itunes.apple.com/us/app/gasbuddy-find-cheap-gas-prices/id406719683
Black Kettle National Grasslands In Cheyenne OK offers free camping and the near by Black Kettle Museum aka Washita Battlefield National Historic site is also free. Our OKC zoo will be having a free entrance day this Wednesday. If you do some research you can do so many exciting things and hardly have to pay anything at all.
Free Camping phone app
When you roll into a new town, hit the library and ask when the church page comes out in the local newspaper. Scan the announcements for "pot luck" or "dinner served after the service". You will eat better than any restaurant because "Grandma" cooked it. Local colleges and universities have club meetings all the time and often serve food. International student clubs are some of the best. You will see a lot of pizza and donuts at the run of the mill club meetings. Check the announcement boards at the student union. If the faculty are having a catered event, call up the catering company and see if you can get a 1 day job as a server. You will eat really well, get paid and get to take leftovers with you. Come prepared always to any event with a back pack and lots of large zip lock bags to put stuff in. Keep a cooler in your car.
You will have a lot of fun.