Car rentals are in high demand, but rental car companies haven't yet grown their fleets to fill the demand. This has created a surge in car rental rates. CheapCarRental.net found the top ten most expensive weekly car rental rates from rental services located in airports across the country. Not surprisingly, Hawaii takes the top spot as the state with four of the most expensive car rental rates in the country. Check out this list to see which American cities made the list.

The most expensive city in the country for car rentals this month might come as a surprise. Anchorage, Alaska's average weekly car rental rates for this month are at $1,451. So maybe that Alaska cruise will be better for your wallet in the long run, or just take an Uber everywhere you go.

Lihue, Hawaii is the first of four Hawaiian cities to make this list, which comes as no surprise, as Hawaii especially has had high demand for car rentals, but limited supply. Lihue's weekly rates are at $1,065, making it the second most expensive in the country.

Portland, Oregon makes it in third place, with weekly car rental rates at $965. A pro tip on how to get by in Portland without a car rental is to stay at a hotel in a central location so you can walk, take a taxi or bike anywhere you'd like. Some urban properties also provide free bicycles, so inquire with the hotels you're looking at to see if they offer such things.

Kona, Hawaii is the second Hawaiian city to make this list. In fourth place, weekly car rental rates are at $948. You might want to stick to Ubers or public transportation, which is available across Hawaii.

Honolulu makes it to the fifth spot on this list, with weekly rental rates at $937, just around ten dollars less than in Kona. While it's definitely nice to have your own rental in Hawaii, the official Hawaii tourism website recommends several alternative methods of travel here.

Kahului, Hawaii is located on the island of Maui. It is in sixth place, with weekly rental rates at $895. Because of the rental car shortage across the Hawaiian islands, it might be better to stay somewhere more centralized or in an area that offers its own form of transportation.

The second city called Portland on this list is located on the East Coast this time. Portland, Maine is reporting weekly rates of $840 for the month of August, making it the seventh most expensive city for car rental rates in the country.

We return to the West Coast for the eighth-most expensive city for car rental rates, which is Seattle. Seattle is reporting weekly rates of $746, which is still quite elevated. A tip: stay at a hotel in a centralized location that offers bicycle rentals or free transportation, which will help offset some of the costs of renting a car. While these hotels are most likely more expensive to stay in, they might end up being cheaper than renting a car.

Perhaps the most unexpected city on this list, Boise, Idaho is reporting weekly car rental rates of $701. Using alternative methods of transportation is going to be the best recommendation for travelers staying in this city.

Minneapolis, Minnesota ends the list in tenth place. With weekly car rental rates of $690, it's still pricey renting a car there. A good tip is to use alternative methods of travel, especially during the summer, like walking, biking or public transportation.