Waimea Canyon State Park
Carved over countless centuries by the Waimea River and the forces of wind and rain, Waimea Canyon is a dramatic gorge nicknamed the "Grand Canyon of the Pacific"—but not by Mark Twain, as many people mistakenly think. Hiking and hunting trails wind through the canyon, which is 3,600 feet deep, 2 miles wide, and 10 miles long. The cliff sides have been sharply eroded, exposing swatches of colorful soil. The deep red, brown, and green hues are constantly changing in the sun, and frequent rainbows and waterfalls enhance the natural beauty.
This is one of Kauai's prettiest spots, and it's worth stopping at both the Puu ka Pele and Puu hinahina lookouts. Clean public restrooms and parking are at both lookouts.