Kauaʻi is 5.5-6 million years old. During that time, wind and water have carved away the original volcano to reveal layers of old eruptions—it’s like looking back in time. The brilliant red earth tones of the cliffs, softened by the greens and golds of plants, change as the sun moves over the gorge.
The name Waimea refers to the reddish water (wai = fresh water, mea = red) that floods from the canyon after heavy rains. Think about the forces of nature working over eons of time, building then carving away layer upon layer of lava to expose the interior of Kauai’s original volcano.
Kauaʻi is the high-island stage of an eroding volcano. After this stage, the Hawaiian islands erode down to the Northwest Islands, which are uninhabited low islands and shoals extending 1500 miles beyond Kauai. These are now part of a newly designated wildlife preserve.
Erosion of the canyon walls has been accelerated by goats, now wild in Waimea Canyon. Goats were introduced to Kauai in 1792 by English sea captain George Vancouver. Hawaiian island ecosystems evolved without any four-footed mammals which have been extremely destructive since their introduction.
One of the best resources for understanding the geology of Kauaʻi is “Kauai’s Geologic History, A Simplified Guide” by geologist Dr. Chuck Blay, which you can purchase by Clicking Here.