Cruise up the Wailua River to the fern covered grotto. While at the grotto, local Hawaiian musicians play traditional songs.
The trip takes 40 minutes with any one of many companies on a long, flat-bottom riverboat. Boats depart from the south side of the river every 30 minutes. The Wailua River is the only navigable river in Hawaii. You will also see kayakers, motor boats and water skiers. We went on Waialeale Boat Tours which departs for the grotto every 30 minutes - cost is $15/person. While cruising at a leisurely pace to and fro from the Grotto, we were entertained with Hawaiian musicians and hula dancers. Great trip. There are other companies and you can go directly to the marina for your pick of companies to cruise with. At the marina is the Smith's Tropical Paradise also.