During any trip, it's important to stop often so your pet can stretch its legs, relieve itself and burn off some excess energy.
Although water is fine, don't feed your pet in a moving vehicle. It's actually best to feed it no less than three to four hours before your trip begins, to minimize motion sickness. If your pet needs to eat during the duration of the trip, feed it at a rest stop and give it some time to digest.
Speaking of rest stops, when you do stop, never let your pet out of the vehicle without a leash. In an unfamiliar place, animals can act unpredictably and tragedy can occur. Don't put your pet at risk -- keep it on the leash.
Always park in the shade. And never leave an animal unattended in a parked vehicle. On a warm day, the temperature in your car can rise to 120 degrees Fahrenheit (49 degrees Celsius) in minutes, even with the window open [source: Humane Society].