Nā Pali Coast State Park encompasses is located along the north-west side of Kauaʻi In the United States, (Kauaʻi is the oldest inhabited Hawaiian island). The Waterfall Cave, is situated just off the shore of Nā Pali, there are guided tours on zodiacs that go into the cave where you can see this amazing waterfall, Nā Pali cost is maybe the most beautiful coastline of the Hawaiian islands.