Hawaii: Kauai’s hidden Fern Grotto is just a boat ride away on the Wailua River

Smith’s Fern Grotto tours in Kauai, Hawaii

Ti plants grow in front of Fern Grotto in Wailua River State Park on Kauai. The hidden cave is accessible only by boat.

(Jay Jones / For The Times)

Boat tours abound in Hawaii, but there’s only one that journeys inland -- away from the ocean -- and into a tropical rainforest.

The Smith family has been taking visitors to Kauai on entertaining, informative and spectacularly beautiful journeys along the Wailua River since 1946.

“My folks started the boat tours right after the war,” Walter Smith Jr., the family patriarch better known as “Freckles,” told me. Now 81, he began working in the family business after school when he was 12.


As tourism to the island resumed, Walter Smith Sr., and his wife, Emily, began offering tours using a rowboat and a borrowed outboard motor. The destination remains the same today as it was 70 years ago: Fern Grotto, now part of Wailua River State Park.

Dozens of guests step aboard large, open-air crafts (they have roofs to shelter passengers from the unpredictable rain showers) to the grotto, which is only accessible by boat. From a landing, visitors take a short stroll through colorful vegetation, including plenty of bright red ginger, to a large deck overlooking the grotto.

The small cave sits at the base of a fern-covered cliff. Water trickles down from a spring above.

On a large wooden deck, tourists are greeted by the Smiths’ employees, who entertain with music, hula and storytelling. It turns out the scenic setting has been the site of thousands of weddings.


Since 2006, however, the state has mandated that, for safety reasons, ceremonies be performed on the platform instead of inside the cave.

Rivers are rare in Hawaii, and the Wailua is the only one that can be navigated by boats bigger than a kayak. The Smith family’s motorized boats share the wide waterway with canoeists, kayakers, stand-up paddlers and fishermen.

Guide Josh Horner told his guests that the river is full of catfish, tilapia, tuna and even barracuda.

“They’re harmless,” Horner said of the barracuda. “They’re only about a foot long.” 

Rainwater from one of the wettest places on Earth feeds the river, which begins on the slopes of Mount Waialeale, 20 miles inland. The 5,000-foot mountain averages a whopping 450 inches of rain a year. Guests learn that several ancient Hawaiian temples once dotted the lush riverbank.

The entrance to the Smiths’ operation (the family also operates a tropical garden and a luau) is just south of the bridge along Kuhio Highway (Route 56).

The tours, operated four times a day, last about 1 1/2 hours. They include a 30-minute stop at the grotto.

Tickets are $20 for adults and $10 for kids, and there’s a 10% discount when purchased in advance online.


Info: Smith’s Fern Grotto tours, (808) 821-6895


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