Planning and patience is required to train your cat to love traveling. Even so, not all cats will learn to share 
your passion for the road. Some will love it, others will merely tolerate the journey. A few will always and forever be happier in a kennel or with a petsitter. Just don’t write off the idea of sharing the adventures without taking time to introduce the cat to the idea properly. Personally, I had two cats that traveled over 10,000 miles with us, and I currently have a dog that hates riding in the car. No amount of rewards or slow introductions changes his mind.
First of all, let me explain that I will never fly any animal anywhere, unless it’s a service animal that is inside the cabin with his/her person. The type of traveling discussed in this post is in an auto or recreational vehicle. To keep everyone safe and eliminate risk of escape, along with eliminating unnecessary stops, I like a medium to large dog crate (brands vary in what the sizes measure). The ones we like are large enough for the food and water cups at the front and a small, disposable, travel size litter pan at the back with a little blanket in between. It should fasten securely, be properly tied down in the vehicle, and be hard-sided. With this set up, you never have to take your cat out of the carrier, unless you are in a hotel or parked for the night and able to monitor them closely.
For the initial training, the litter pan isn’t necessary since you’ll just make short trips and do errands that are nearby. It’s not a bad idea to have it in there anyway, unless you plan to have to carry it into a store or the vet’s office and want to lighten the load. In my case, I can no longer carry anything with that much size and weight. Solution? A substantial luggage carrier to strap it on and roll it. There are nice sturdy travel bags with wheels for short trips, but longer trips and full vacation travel requires a better set up, like the one above.
Initially, I recommend using the set up you’ll use to travel. Then, keep that crate and the entire set up, even the litter pan, open and available to the cat at home too. Let it become familiar and comfortable. Put in a catnip toy. Spray it with Feliway. Feed the kitty in those bowls (be sure the door is secure and stable, but start with it open). Whatever you do, don’t wash the kitty’s favorite blanket or toys before leaving. That destroys all of the good familiar odors.
Getting used to riding is a slow, multi-stage process. Allow at least a week for each stage, and be sure you really are doing it every day or more than once a day. No cheating and then, complaining that the cat isn’t adapting. Start by just sitting in the driveway in the car listening to the radio and talking to the cat, maybe feed a few treats too. Next, go to the car and start the engine while you play music (soft rock or talk, nothing jarring and scary please), visit with kitty, and offer treats. Then, progress to just driving forward and backward a few times in the driveway, continue with music and talking. Offer treats when put in the carrier and after the “trip.”
The next steps begin to get you on the road. Now, it’s time to drive around the block at least once a day. Remember, each step requires a full week. If you rush, kitty doesn’t have time to decide that this experience is a pattern and is not harmful. Then, proceed to short trips that are a bit further. Last of all, begin taking kitty along on errands, but do not leave the kitty in the car unless someone else is with you to continue talking, offering treats, and monitoring the cat. You should now be ready for some short trips and even a longer one, if your cat seems unconcerned about the riding experience by now.
One last tip, don’t forget to keep kitty in practice for traveling. It’s not a one time and it’s done training exercise. If you don’t travel for two years and only take the cat to the vet, Mr/Ms Kitty will not be travel ready for the next vacation. A microchip and a secure H-harness are also mandatory accessories for our cats while traveling.
Have fun and enjoy sharing your travels.