When most mainlanders think about Hawaii, they likely imagine the crowded beaches of Waikiki or the historic sites of Pearl Harbor.

But Oahu — the island that's home to both Honolulu and Waikiki Beach — offers much more than these well-trod tourist destinations. And travelers have further treasures to explore when venturing to other Hawaiian islands, like Maui.

Here, we compare two favorite Hawaii tourist destinations, Maui and Oahu, to help you decide which is better for the vacation you're seeking. Or, perhaps, to help you determine if you should visit both.

Key differences between Oahu and Maui

The main differences between Oahu and Maui are the crowds and types of tourist destinations.

Oahu

Oahu, home to capital city Honolulu, is generally more crowded than Maui. It boasts the best-known destinations in Hawaii.

You can book one of the many hotels on Waikiki Beach, visit the U.S.S. Arizona Memorial, and explore the views from Diamond Head State Monument.

Rent a car and drive up to the North Shore to find some of the most famous surfing waves in the world. And the center of Oahu hosts the Dole plantation — where tourists can visit the headquarters of the company synonymous with pineapples.

Maui

Meanwhile, Maui offers a much more outdoorsy experience because of its pristine beaches and towering volcanic peaks.

Maui offers some of the most luxurious resorts and best golf courses in Hawaii. Plus, the massive 10,023-foot Haleakala volcano — the largest dormant volcano in the world — offers such spectacular sunrise views from its peak that you'll need to make a reservation to see for yourself.

The mountainous terrain creates spectacular waterfalls. All of these outdoorsy draws led Maui to be voted the "Best Island in the World" for more than a decade by readers of Condé Nast Traveler and Travel + Leisure magazines.

Size comparison

Home to the Hawaiian capital of Honolulu, Oahu is the most populous Hawaiian island, with just over one million residents. However, Oahu is just the third-largest of the Hawaiian islands in physical size, behind Maui and the so-called "Big Island" of Hawaii.

Although Maui is a larger island than Oahu in terms of area, it’s just the third most-populous Hawaiian island, with only about 150,000 residents. With a bigger size and much smaller population, Maui offers a lot less density and more land for visitors to explore.

Is it cheaper to fly to Oahu or Maui?

Travelers from the mainland U.S. can score a deal to either Oahu or Maui.

At the time of writing, flights to Maui are running a bit cheaper than Oahu. However, when flying during off-peak times, neither destination will break the bank. For example, you can find flights from San Francisco to either island for under $250 round-trip.

Of course, flights to Hawaii aren't always cheap. During peak travel times, airfares will be much higher for either island. When comparing prices, remember that there's only one trick to traveling cheaply — flexibility.

Most U.S. airline loyalty programs have now switched to dynamic award pricing. That means award prices generally rise and fall with cash rates. Whenever booking award flights, it's worth comparing award rates versus cash rates to see which makes more sense.

Flying between Maui and Oahu

If you don't want to choose between Maui and Oahu, the good news is that you can easily visit both islands. Most airlines will let you book one-way flights to Hawaii for half of the round-trip price.

Or, you can book an open-jaw itinerary where you fly into Oahu and back home from Maui (or vice versa).

Once in Hawaii, hopping between Maui and Oahu is easy and relatively cheap. The 100-mile flights between Maui and Oahu typically take just 40 to 45 minutes.

Three airlines currently fly between Maui and Oahu:

Hawaiian Airlines — between Honolulu and Kahului.

Southwest Airlines — between Honolulu and Kahului.

Mokulele Airlines — from Honolulu to Kahului and Kapalua.

And flight prices can be downright cheap. Flights between Honolulu and Kahului are often priced at just $39 each way — particularly if you book in advance.

Using points and miles to fly between Maui and Oahu

Because of airline partnerships, travelers have plenty of ways to use points and miles to fly between Maui and Oahu.

The best option is likely to be using Southwest Rapid Rewards points. Cheap flights are where Southwest's revenue-based redemption program really shines. If you select one of the cheapest fares, you can pay as few as 2,163 Rapid Rewards points, plus $5.60 in taxes and fees, to hop between Maui and Oahu.

In addition to offering awards through its HawaiianMiles program, Hawaiian Airlines partners with several mainland airline loyalty programs. Here are the award prices for intra-Hawaiian island flights by loyalty program:

Hawaiian Airlines: 7,500 HawaiianMiles.

American Airlines: 7,500 AAdvantage miles.

Delta Air Lines: 7,500 SkyMiles.

United Airlines: 7,700 MileagePlus miles.

Maui vs. Oahu, recapped

Travelers looking to escape to Hawaii won't be disappointed by either Maui or Oahu. But, there are important differences between Maui and Oahu vacations.

If you're looking for a typical Hawaiian tourist vacation, Oahu offers Waikiki Beach, historical memorials and modern culture. Meanwhile, travelers should head to Maui to enjoy outdoorsy adventures, from snorkeling to hiking volcanic peaks.

The important thing to remember is that you aren't limited to just one Hawaiian island. If you're flying all the way out to Hawaii, consider working both Maui and Oahu into your travel plans. Flights between Maui and Oahu are frequent and relatively cheap. Try both islands and see for yourself which one you prefer.