 Known also as the "Garden Isle", Kauai lies 105 miles (169 km) across the Kauai Channel, northwest of Oahu.This island is the site of Waimea Canyon State Park.The United States Census Bureau defines Kauai as census tracts 401 through 409 of Kauai County, Hawaii, which comprises all of the county except for the islands of Kaʻula, Lehua and Niihau.