The best way to experience all of Kauai's stunning beauty is to get in a car and explore. The 15-mile stretch of Napali Coast, with its breathtaking, verdant-green sheer cliffs, is the only part of the island that's not accessible by car. Otherwise, one main road can get you from Barking Sands Beach on the West Side to Haena on the North Shore.
Asking for directions will almost always produce a helpful explanation from the locals, but you should be prepared for an island term or two. Instead of using compass directions, remember that Hawaii residents refer to places as being either mauka (toward the mountains) or makai (toward the ocean) from one another. Hawaii has a strict seat-belt law. All those riding in the vehicle must wear a seat belt. The fine for not wearing a seat belt is $112. There is also a law forbidding the use of handheld devices while driving. Jaywalking is also common in the Islands, so please pay careful attention to the roads. It also is considered rude to honk your horn, so be patient if someone is turning or proceeding through an intersection.
While driving on Kauai, you will come across several one-lane bridges. If you are the first to approach a bridge, the car on the other side will wait while you cross. If a car on the other side is closer to the bridge, then you should wait while the driver crosses. If you're enjoying the island's dramatic views, pull over to the shoulder so you don't block traffic.
You can count on having to pay more at the pump for gasoline on Kauai than on the U.S. mainland. There are no gas stations past Princeville on the North Shore, and no stations past Waimea on the West Side, so if you're running low, fuel up before heading out to the end of the road.
On Kauai there are no parking meters, parking garages, parking tags, or paid parking. If there's room on the side of the road, you can park there. A good rule of thumb is if there are other cars parked in that area, it's safe to do the same.
Kauai has a relatively well-maintained highway running south from Lihue to Barking Sands Beach; a spur at Waimea takes you along Waimea Canyon Drive to Kokee State Park. A northern route also winds its way from Lihue to the end of the road at Haena, the beginning of the rugged and roadless Napali Coast. Opt for a four-wheel-drive vehicle if dirt-road exploration holds any appeal.
If you find yourself in an emergency or accident while driving on Kauai, pull over if you can. If you have a cell phone with you, call the roadside assistance number on your rental-car contract or AAA Help. If you find that your car has been broken into or stolen, report it immediately to your rental-car company and an agent can assist you. If it's an emergency and someone is hurt, call 911 immediately and stay there until medical personnel arrive.
Should you plan to do any sightseeing on Kauai, it is best to rent a car. Even if all you want to do is relax at your resort, you may want to hop in the car to check out one of the island's popular restaurants.
While on Kauai, you can rent anything from an econobox to a Ferrari. Rates are usually better if you reserve through a rental agency's website. It's wise to make reservations far in advance and make sure that a confirmed reservation guarantees you a car, especially if you're visiting during peak seasons or for major conventions or sporting events. Rates begin at about $25 to $35 a day for an economy car with air-conditioning, automatic transmission, and unlimited mileage, depending on your pickup location. This does not include the airport concession fee, general excise tax, rental-vehicle surcharge, or vehicle license fee. When you reserve a car, ask about cancellation penalties. Many rental companies in Hawaii offer coupons for discounts at various attractions that could save you money later on in your trip.
In Hawaii you must be 21 years of age to rent a car, and you must have a valid driver's license and a major credit card. Those under 25 will pay a daily surcharge of $15–$25. Request car seats and extras such as GPS when you book. Hawaii's Child Restraint Law requires that all children three years and younger be in an approved child safety seat in the backseat of a vehicle. Children ages four to seven must be seated in a rear booster seat or child restraint such as a lap and shoulder belt. Car seats and boosters range from $5 to $8 per day.
Your unexpired driver's license is valid for rental for up to 90 days.
Since the road circling the island is usually two lanes, allow plenty of time to return your vehicle so that you can make your flight. Traffic can be bad during morning and afternoon rush hour. Give yourself about two hours before departure time to return your vehicle.