Mermaid Cave in Oahu, Hawaii Reveals More Than 1 Reason to Visit

As a little girl, I remember running around the house belting Part of Your World, rocking Ariel’s enviable side-swoop bangs, achieved by the grace of my very patient mother, a full can of hairspray, and a gigantic round brush.

It should come as no surprise that when putting together the itinerary for my mother-daughter trip with my youngest, Avery, I couldn’t pass up the opportunity to venture out in search of Oahu’s Mermaid Cave.

While accessible, the cave is still considered a hidden treasure. A great bonus? The beach it’s located near is absolutely stunning and makes for a perfect location to spend the day swimming or enjoying a picnic.

Directions to Mermaid Cave

Located on the Western shore of Oahu, about an hour from Waikiki Beach, Mermaid Cave is relatively easy to find if you’ve got Google Maps and a good pair of water shoes.

The best time to go is during low tide so you can swim in the tunnels but still have areas of rock to sit on within the cave (check out tide times here before heading out).

Head to Nanakuli Beach Park, also known to locals as Kalaniana’ole Beach Park. About 40-acres in size, the park has restrooms, changing rooms, beautiful views of the water and mountains, and of course, your access point to Mermaid Cave.

Driving in, keep an eye out for the park entrance; initially, we drove right past it, expecting to see more than a few small buildings and parking lot.

The cave is just a 5 to 7 minute walk from the parking lot, heading toward the rocky side of the beach. You’ll be treading through sand the first part of your journey, but soon find yourself navigating lava rocks as you get closer. Avery (10 at the time) had no issues getting to the opening of the caves even though we had read the trek across the rocks was a bit difficult.

Looking for a more daring route? During low tide, you can also snorkel into the cave as the tunnels flow out into the ocean.

Exploring Nanakuli Beach Park

We came, we saw … we didn’t dive in.

While getting to the caves was not as tricky as I had heard, getting into them posed a bit more of a challenge, especially since with Avery in tow I had to be somewhat of a responsible adult.

To get into the caves, your best bet is to jump in through one of the top holes or head to the edge of the cliff, jump into the ocean, and then swim in through one of the tunnels.

While normally I would have taken the plunge, the jump was a bit much for Avery and we decided to hang back and watch as a few people swam in and out, grabbing lots of photos for the Gram.

Luckily for us, there was no downside to not making it into Mermaid Cave.

The beaches in Waianae greeted us with some of the bluest water I’ve ever seen and even midafternoon on a beautiful, sunny day the crowds were nowhere to be seen.

And so, we swam.