I love free campgrounds. Beyond the fact that it doesn’t break the bank, I personally like sleeping without anyone else around me, and typically free camping spots offer this solitude. That way, when we go to bed early, other campers aren’t keeping us awake with their partying, and when we get up early, we aren’t waking them up with our noise (ever tried to keep a 1-year-old quiet when s/he’s really not happy about waiting for breakfast?!?)
In general, there are two ways to camp, out-of-the-vehicle and in-the-vehicle:
Out-of-the-vehicle camping: Usually, this means setting up a tent, although in some places (like Death Valley) you can just put down a tarp and sleep under the stars (that’s always a treat—ever stargazed while going to sleep?) Of course, an animal could decide to sleep with you (like the time a raccoon decided to climb into the sleeping bag with one of the members of my group!), but I don’t get the impression this happens real often, at least in Death Valley.
In-the-vehicle camping: Often this means sleeping in a camper, but you don’t have to have a camper to sleep in your vehicle. I’ve seen people (usually singles) do it in compact cars, but any vehicle would work. We use a full-sized van, and have found it to work quite well. You can sleep on the back seats (one member of my group told me that it’s far more comfortable than sleeping in a tent, even with a cot), or you can take out the back seats and sleep on the floor (also comfortable). The other great thing about a full-sized van is that it is high-clearance, and can go places a car or camper couldn’t possibly get to.
There are several options for those who do either kind of camping. Probably the most universal is National Forest/National Grassland/Bureau of Land Management (BLM) areas. The policy of these areas is that if you drive down a dirt road for ½ a mile, you can camp by the side of the road (assuming there’s a place to do it, and you’re not trampling vegetation, there aren’t any signs telling you not to, etc.). In the past, we have found that, especially in popular areas, there is a campsite at exactly ½ a mile down the road. Another possibility is that some national parks and monuments allow you to go “free range” camping (camp wherever you want within reason). Death Valley National Park, Mojave National Preserve, and Padre Island National Seashore are three parks where this is allowed, as does Anza-Borrego Desert State Park. Check these parks’ websites for specific information. Always, do not camp if there are signs that forbid camping.
For in-the-vehicle campers, there are more options available. First, Walmarts. By company policy, campers can spend one free night in the parking lot of Walmart stores (I even read about it in a DK travel guide!). Occasionally, a town will set up an ordinance that will forbid overnight parking in the Walmart parking lot, but usually this is not the store’s idea. However, please obey signs and do not camp where there are signs requesting you not to. At one point we found a Rand McNally Road Atlas published especially for Walmart that listed all of the Walmart stores in the US, Canada, and Mexico. That’s great when we’re looking for someplace to sleep, especially because they mark the ones that are within a mile of a major highway. You can even “pay” the store for letting you sleep there by doing any shopping you need to do in the store, or buying your morning cup of coffee at the McDonalds that sometimes is in the Walmart store.
Some states allow campers to park overnight in their rest areas. These are very convenient for travelers, and can be quieter than Walmart parking lots (although not always). When we do this, we typically park in the truck section, because the trucks are also spending the night. The trucks also create “white noise” that make it easier to sleep. You might want to hang curtains in the windows of your vehicle, though, because the lights can be extremely bright. Alternatively, you may be able to park in a “truck parking area” that are available in some places. However, I wouldn’t consider these as safe as the other options mentioned. Walmarts typically have security cars driving around while the store is open (sometimes 24 hours). Currently, Arkansas, Arizona, Idaho, Kansas, Missouri, Montana, New Mexico, Nevada, Oklahoma, Oregon, Rhode Island, Utah, Texas, and Washington allow you to sleep overnight in their rest areas. Even in these states, there may be specific rest areas that forbid overnight parking.
There are some safety tips you should follow when sleeping in places like these. First and foremost, never, ever open your door to anyone. If someone comes over to speak to you (especially if it’s the police asking you to leave), open your window to talk to them, but don’t open the door. You never know who the person might be. Second, don’t camp alone. This may be hard for some travelers, but even in my own large group, we do our absolute best not to go off on our own. There’s definitely power in more than one. Third, tell someone where you’re going, so they’ll at least have an idea of your whereabouts. We e-mail family members about our next moves, to let them know we’re ok, to tell them what a great time we’re having, and so they know where we’re going. You could also leave an itinerary with someone, but that will only work as long as you stick to it. We’re constantly changing our itinerary, so we e-mail whenever we’re in civilization. Last, take a cell phone with you. If you find yourself trapped in some way, you can call for help.