Sightseeing
Fern Grotto: A Wailua River Boat Ride
By Rick Kennerknecht · Updated October 2026
The Fern Grotto is a natural lava-rock amphitheater draped in hanging ferns, tucked up the Wailua River and reachable only by boat. The cruise there, with Hawaiian music, hula, and the story of the river valley of the kings, is a Kauai classic that has welcomed visitors for generations. Smith's boats have been running again since September 24, 2026. It is gentle, scenic, and ideal for families, older travelers, and cruise-day guests.
Hurricane Lowell recovery (as of October 21, 2026): Haena State Park reopened October 15 (reservations required), but Kokee and Waimea Canyon state parks, most other Kauai state parks, the Kalalau Trail past mile 2, all state camping, and Secret Falls remain closed, and Port Allen's small boat harbor is only partly open. See our what's open on Kauai page, and check DLNR state parks, openkauai.org, and your tour operator before you go.
The boat cruise
Smith's Motor Boat Service runs the flat-bottomed riverboats up the Wailua from the marina near Kapaa, back in service since September 24, 2026. The round trip takes about 80 to 90 minutes, with live Hawaiian music and hula on board and narration about the valley's history. The water is calm, so it is comfortable for everyone.
The grotto itself
At the landing, a short paved path leads to the grotto, a shaded rock hollow hung with sword ferns where couples have long exchanged vows. Since Hurricane Lowell, only Smith's boats may land here, so kayakers cannot stop. Its lushness depends on recent rain; after dry spells the ferns thin out, but the setting stays atmospheric.
Cost and booking
Tickets are $35 for adults and $17.50 for children, plus state park fees, which makes it one of Kauai's better-value outings. Tours depart several times daily; booking ahead is smart in peak season and on cruise-ship days when demand spikes.
Who it suits
Because there is no strenuous hiking or paddling, the Fern Grotto is a good fit for grandparents, young kids, and anyone wanting a relaxed, cultural half-morning. It also runs rain or shine, making it a reliable pick when the weather is iffy.
Pair it with Wailua
Combine the grotto with nearby Wailua Falls, Opaekaa Falls, and the coastal bike path for an easy east-side day, all within a few minutes of Kapaa and Lihue.
Frequently Asked Questions
By riverboat up the Wailua River from the marina near Kapaa; the grotto is not reachable by road. Smith's runs the tour, and since Hurricane Lowell only its boats may land.
More guides: all Kauai guides · things to do.