California Desert Driving & Vacations

Don't be intimidated by the idea of driving through the desert -- there's nothing in California like the ordeals and rigors required to drive through the African, Asian, or Australian deserts. California being the auto-centric place it is, desert driving is usually safe, convenient, and enjoyable, and you'll see some of the best parts of California, including the Mojave desert, Death Valley, Panamint Valley, and the Owens Valley.

Off the beaten path -- Queen Sheba's Mines In general, since California's deserts are fairly well-populated, desert driving is normally done on reasonably good roads with gas, food, water, and accommodation available at convenient intervals. Unless you're really going off-road driving, most roads will be paved or fairly good condition gravel; many of the most popular routes across the deserts are actually freeways or highways. Gas stations are nearly always within easy reach of wherever you are (but gas will usually be more expensive here than in urban and suburban areas). Most of the larger truck stops and settlements along the highways and freeways will have some sort of cafes and cheap motels as well.

Except during winter, the deserts get really hot, with daily temperatures in the 45 degrees celsius range, and with low to zero humidity. Death Valley is one of the hottest and driest places on earth, and much of the rest of the Mojave isn't particularly cool either. Europeans and Britons by and large will not have much experience with this (and nor will most European cars be designed to cope with this), so try to remember to protect both yourself and your car:

If you're not used to high temperatures, don't drive through the desert in summer.
Do something else -- go on a winetasting tour of the Napa valley, or go to the beach, or do something a little less likely to promote heat stroke. If you have to cross the desert in the summer, stick to the freeways and try to get an air-conditioned car.
Always carry enough water for you and your passengers to survive in the desert if your car breaks down.
If you're going off the beaten track, plan on needing three days' worth of water for each person; otherwise one day is probably sufficient. The amount of water each person uses per day is clearly dependent on the surrounding temperature and humidity. In the middle of summer I always carry at least a gallon (4 litres) for each person per day; during the rest of the year it's probably a fair bit less than this.
Carry additional water for your car's radiator.
California's deserts are often mountainous, and your car may have to rise from near sea level to over 8,000' within a few tens of miles. This does interesting things to your car's cooling system, so be prepared to take it easy and watch the radiator temperature and coolant levels.
Your car should be in good condition, reliable, and physically fairly robust.
You don't need any special sort of car in the desert unless you're going off-road or along some of the worst tracks away from civilization, but you do want to have a car that isn't going to break down, and that has enough clearance and traction to cope with the smaller dirt roads if you're leaving the freeways and highways. Don't attempt to leave the freeways or major highways and roads with a stretch limo, a large RV, or a low-rider, for example.
If your car breaks down in the desert, stay with it.
Don't wander off away from the car unless it's to get help from a clearly-visible call box on the road you're on or an obviously-inhabited building within a few minute's walk. Any further than this and you have a good chance of never being seen alive again (and if you have any doubts about how far away something is, don't leave your car).

Try to find some shade near the car, or try to stay in the shade of your car, and don't waste energy and water with unnecessary movement or exertion. This advice holds for break-downs anywhere in the desert, whether on the side of a major freeway or off the beaten track. If you do leave you car, make sure it's not in the way of other traffic, lock it, and leave a clearly-visible note under the windshield spelling out who you are, where you're headed, and when you left. Do this whether you're leaving because a passing traveler has just offered you a ride into the nearest town so you can call the AAA, or because you've just given up after a few hour's waiting and have stupidly decided to walk the 60 miles back to Barstow on your own.

The less well-traveled a particular route is the more likely it is that a passing vehicle will stop and offer assistance. The corollary to this is that if you come across a breakdown or accident in the middle of nowhere, you should be prepared to help as best you can.
Try to have a car with air conditioning. Having said this, don't overwork your car if it's small or under-powered by using the air conditioning all the time -- turn it off while going up steep or long hills, for example.
When you're off the freeways and major highways, fill up with gas and water whenever you can -- don't just assume the next gas station will be open or that the next settlement even has one. You can never have too much gas or water in the desert.
Deserts actually get quite cold during the night; in winter the temperatures can go well below freezing. Always carry enough clothing or blankets to keep warm in these conditions (you'd be surprised at the number of tourists who don't realize this and who end up complaining about the cold!).

Unless you're in a hurry, don't blindly stick to the freeways -- there are lots of good roads that parallel or take more scenic back-country routes away from the freeways. For example, Interstate 40 between Barstow and Kingman (Arizona) parallels the old Route 66 highway, an authentic American historical treasure. You'll see a lot more driving along this part of the old Route 66 (now known as the "National Trails Highway") than you would if you just go straight down I-40: you'll be able to stop next to the road pretty much wherever you like, look at the scenery, take photos, or just walk around and explore the ghost towns and the natural landscape (there are volcanic craters, sand dunes, dry lake beds, etc. all within walking distance of the road).

Don't be put off by the relative remoteness of the area and the apparent lack of traffic on some of these roads -- most roads that are marked on an average California desert road map are well-enough traveled that if you do get into trouble, someone is likely to come along within an hour or two (the CHP, for example, patrols the old Route 66 at least once or twice a day).

On the other hand, don't blindly take just any old route away from the freeways or highways. Unless you're pretty sure the road is good (for example a trusted map of the area deems it suitable for the sort of car you're driving), or you know you've got enough gas to turn around and come back from any point along the way if the road turns out to be too much for your car, don't go down a side road or track without asking locals about it (and always take their advice with a grain of salt). Similarly, if you don't know how to read a map or navigate using topographical information, don't go off-road or away from the major marked roads. Always make sure you understand the map you're using, that it's up-to-date and accurate, and that you really are where you think you are when you're using it.