Take a leisurely cruise down the Wailua River to the botanical beauty of the Fern Grotto. Wailua River is known as "the only navigable river" in all Hawaii. The rivers fresh water pours from the Mt. Wai'ale'ale, one of the wettest spots on the plant.Lands along the river were the sacred capital of ancient Kauai and the birth place of the island's ali'i, or royalty. During the two mile river journey, you'll hear songs and stories of ancient Hawaii and enjoy learning the hula during a lesson provided by a young hula dancer. The Fern Grotto is a geological wonder of Kauai. Ferns grow upside down from the roof of the grotto, which was formed millions of years ago. Native Hawaiian plants and colorful exotic tropical plants provide a rain-forest atmosphere. A visit to the overlook at Opaekaa Falls , the most accessible waterfall on the island, will secure your love of Kauai, our garden island.