Waimea Canyon

Waimea Canyon is what happened when Kauai collapsed. The island is the oldest of the big Hawaiian volcanoes — five million years of lava built it — and four million years ago the side came down, the flank failure that left the depression the Waimea River has been cutting ever since. The canyon is the wound: ten miles long, three thousand feet deep, the walls showing the layered lava flows of the shield volcano's interior in red and orange and black.

Mark Twain called it the Grand Canyon of the Pacific when he saw it in 1866 — the comparison stuck because it's accurate. The canyon is a third the Arizona one's depth but the colors are more varied — the red dirt that gives Waimea its name, 'reddish water,' stains the river and the cliffs, and the green of the vegetation against the rock makes the walls look painted. The scale is the Pacific's version: the canyon cuts into Mount Waiʻaleʻale, the crater rim that is one of the wettest places on earth.

The water is the architect — Waiʻaleʻale's summit gets over four hundred inches of rain a year, and the runoff has been carving the canyon since the collapse opened the slope. The dikes in the walls are the volcano's plumbing exposed — the vertical lava-filled fissures that fed the flows now stand as dark ribs in the red rock. The canyon is still being cut; the river in the bottom is the same water that's been making it for four million years.

Waimea Canyon is the archive's geology file — the volcano that fell apart and the river that's been explaining the collapse ever since, the canyon that shows the inside of the mountain because the mountain's side is gone.