The Cave Guide

Fern Grotto

Hawaii
1 hr
on the main tour
$35
adult ticket

A grotto reached by a two-mile open-air boat ride up the Wailua River on Kauai, then a short walk through the rainforest.

The story

The Fern Grotto was formed millions of years ago. In 1946, Walter Smith, Sr. and his wife, Emily, started a family business with a small rowboat and a borrowed outboard motor, sharing songs and legends of the Wailua River Valley. Four generations later, the family continues the tradition of sharing their love of Kauai and its rich cultural heritage. The tour to the Fern Grotto includes a river cruise and a nature walk.

History source: smithskauai.com.

What you'll see

  • Fern Grotto
  • Rainforest
  • Native Hawaiian plants
  • Exotic tropical plants

Tickets and timing

Adults
$35, plus state park fees ($5 per person, $10 parking) for non-residents
Kids
$17.50
How long it takes
1 hour 20 minutes round trip
Hours
Boats at 9:30am, 11am, 2pm and 3:30pm.
Booking
Call 808-821-6895 or buy online.

Getting around underground

The walk
A short nature walk through the rainforest to the Fern Grotto.

Getting there

Fern Grotto is in Hawaii.

Parking: Parking fee is $10 per vehicle, paid directly to the State upon arrival.

Directions in Google Maps

Distances are straight-line from each city center.

Before you go

  • Take the 3:30pm boat if you're staying for the luau.
  • State park fees are card only; Hawaii residents with ID are free.

Questions people ask

How long does a visit to Fern Grotto take?

1 hour 20 minutes round trip

Do you need to book Fern Grotto in advance?

Call 808-821-6895 or buy online.

Listed in: cave boat tours

Checked on 2026-10-22 against smithskauai.com (Fern Grotto page). Prices and hours change, so confirm on the official site before you drive out.

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