Introduction to Wailuku River State Park: Rainbow Falls, the most famous attraction in Wailuku River State Park, is 80 feet (24 meters) high and is named after the rainbow formed in the surrounding mist. In addition, the water pool, known as the "Boiling Pot", will constantly appear foam, making it look like it is boiling. It is connected to a stepped cascading waterfall. The basalt lava flows through and slowly cools to form hexagonal rock pillars, which is beautiful. And magical.