Waiānuenue means rainbow water and this Big Island falls earns every letter of that name

It’s named after rainbow water

Rainbow Falls drops 80 feet into a wide turquoise pool just outside downtown Hilo on the Big Island. You can see it from a paved, wheelchair-accessible platform steps from where you park your car.

The falls sit inside Wailuku River State Park, a 16.3-acre stretch along the Wailuku River that holds volcanic geology, Hawaiian mythology and one of the best banyan trees on the island.

In Hawaiian, the falls are called Waiānuenue, and the translation tells you exactly what to expect.

Hawaii’s longest river carved these falls from lava

The Wailuku River runs 28 miles from the slopes of Mauna Kea down to Hilo Bay, making it the longest river in all of Hawaii. Its name translates roughly to “destroying water,” and the river earns it.

The channel follows the boundary between lava flows from two massive volcanoes, Mauna Kea and Mauna Loa.

About 10,000 years ago, according to the U.S. Geological Survey, a Mauna Loa lava flow entered the river and created the rock ledge that forms the falls today.

That same flow shaped the lava cave hiding behind the curtain of water.

Show up at 10 a.m. for rainbows on cue

On clear mornings around 10 a.m., sunlight catches the mist kicked up by the falls and throws vivid rainbows across the pool. That light show gave the waterfall both its Hawaiian and English names.

If you want the best chance, aim for a sunny morning and get there early. The falls change with the weather, too.

After heavy rain, the water spreads wide and thunders down the ledge. During dry stretches, it narrows to a single stream.

Even without a rainbow, wild ginger, monstera and mango trees crowd the view.

A goddess made cloth in the cave behind the falls

Hawaiian tradition says the lava cave behind Rainbow Falls belonged to the goddess Hina, mother of the demigod Maui. She spent her days inside pounding bark into kapa cloth while the mist hid her from view.

A giant moʻo, a lizard creature named Kuna, lived upstream and grew obsessed with her. When Hina refused him, Kuna hurled boulders over the falls and tried to flood the cave.

Hina called out for help, and Maui paddled to the Wailuku River, split the damming boulder and saved her.

Maui chased the monster into boiling water

After freeing his mother, Maui followed Kuna upstream along the Wailuku River.

The moʻo hid in a series of deep pools above the falls, but Maui asked the volcano goddess Pele for help. She sent hot stones into the water.

The pools began to boil, forcing Kuna to the surface, where Maui killed him.

Hawaiians say those pools are the same ones you can see today, and the legend gave the site its name: the Boiling Pots.

The Boiling Pots churn like a giant cauldron

About 1.5 miles upstream from Rainbow Falls, the Wailuku River drops through a series of large terraced pools called the Boiling Pots. Underground channels carved through layers of volcanic rock connect them.

After heavy rain, water surges through these narrow passages and erupts into the pools, making the surface churn and bubble. You can watch it all from an overlook with parking nearby.

Peʻepeʻe Falls feeds into the Boiling Pots from upstream, and you can spot it from the same viewpoint.

Six-sided basalt columns line the pool walls

The rock walls around the Boiling Pots are lined with hexagonal basalt columns, some standing several feet tall.

They formed when thick lava cooled slowly and evenly, causing the rock to shrink and crack into six-sided shapes. The USGS has compared them to the Giant’s Causeway in Ireland and Devil’s Postpile in California.

Each pool stretches roughly 50 feet across, ground out over thousands of years by swirling rocks and sand.

Look closely at the layers and you can see older gray boulders from one eruption frozen inside younger lava from a later flow.

One banyan tree looks like an entire grove

A short trail from the upper viewing area leads to one of the most impressive banyan trees on the Big Island.

Banyans send aerial roots down from their branches to the ground, and over time, those roots thicken into what look like new trunks. A single tree can spread wide enough to cover an area that looks like a whole grove.

The one near Rainbow Falls has a canopy so dense it blocks out most of the sky. The trail to reach it can get muddy and slippery, so wear sturdy shoes.

Climb the stone steps above the falls

From the main viewing platform, a short path and stone steps to the left climb to an overlook above Rainbow Falls. The view shifts up here.

You look down on the falls from above and see the river flowing upstream. Many people skip this upper area, so it tends to stay quiet.

The trail keeps going past the overlook toward the banyan grove, and the whole walk from the parking lot to the banyan and back takes about 20 to 30 minutes at an easy pace.

The river looks calm but the currents are not

Swimming is not allowed at Rainbow Falls or the Boiling Pots, and the park means it.

The Wailuku River hides dangerous underwater currents, submerged lava formations and sudden water surges from upstream rainfall. Even when the surface looks calm, hidden currents beneath the pools can pull you under.

No lifeguards are on duty anywhere in the park. Warning signs are posted throughout, and you should stay behind all railings and barriers.

This is a river that earned the name “destroying water.”

Gates lock at 6 p.m. and you pay by card only

Both sections of the park open daily from 7 a.m. to 5:30 p.m., and the gates lock at 6 p.m. As of January 2026, non-residents pay $5 per person, with kids 3 and under free, plus $10 per non-commercial vehicle.

You can only pay by credit card. Hawaii residents with a valid state ID or driver’s license get in free.

One paid entry covers both sections.

Rainbow Falls sits on Rainbow Drive and the Boiling Pots are at the end of Peʻepeʻe Falls Drive, both off Waiānuenue Avenue.

Thirty minutes here and you’ll want to stay longer

You can see Rainbow Falls and the Boiling Pots in as little as 30 minutes, but give yourself an hour or more if you want to explore both sections and the banyan grove.

The park sits on the rainy side of the Big Island, so bring a light rain jacket. Restrooms are near the Rainbow Falls parking lot.

Once you’re done, Hilo has more worth your time close by, including the Hilo Farmers Market, Liliʻuokalani Gardens and the Pacific Tsunami Museum.

Visit Rainbow Falls in Hilo, Hawaii

You can reach Wailuku River State Park in minutes from downtown Hilo on the Big Island.

The park sits off Waiānuenue Avenue, with Rainbow Falls on Rainbow Drive and the Boiling Pots at the end of Peʻepeʻe Falls Drive.

You get the 80-foot Waiānuenue waterfall, the churning Boiling Pots, Peʻepeʻe Falls and ancient banyan trees all on one entry.

The park opens daily from 7 a.m. to 5:30 p.m., with gates locking at 6 p.m. Non-residents pay $5 per person plus $10 per vehicle, by credit card only. Hawaii residents enter free with valid ID.

This article was created with AI assistance and human editing.

Read more from this brand:

• A 5-inch fish scales a 442-foot cliff on Hawaii’s Big Island and nobody talks about it
• Hawaii’s Kilauea recently erupted with fountains as tall as the Empire State Building
• The deadly temple project that turned Kamehameha into Hawaii’s first king in 1791