The island of Molokai is famously known for its sheer, vertical sea cliffs. Reaching heights of over 3,000 feet, these sea cliffs are among the tallest in the world. They’re one of Hawaii’s most photographed landscapes, and are an incredible and breathtaking site. Yet despite their worldwide acclaim, few people know how the Molokai sea cliffs were originally created.
Part of the East Molokai volcano, the land that makes up the Molokai sea cliffs was formed between 1.5 and 2 million years ago when the island first emerged from the sea. While the highest peak on Molokai today is 4,970 feet, evidence suggests that the East Molokai volcano was once nearly 10,000 feet above sea level—the same as Maui’s Haleakala volcano. Largely because of its own weight, however, the East Molokai volcano began sinking into the sea floor after it went extinct. This sinking resulted in peaks that are today about half as high as those that once rose in their place.
As for the formation of the cliffs themselves, geologists point to a massive landslide about 1.4 million years ago that was triggered by instability beneath the ocean’s surface. The landslide caused the northern third of East Molokai to collapse into the sea. The force of the slide was furthermore so strong that it triggered a tsunami with wave heights reaching over 2,000 feet, and shot chunks of land over 100 miles off Molokai’s northern coast. Today, these chunks of land are shown on maps as underwater seamounts.
In the years that have passed since the cataclysmic landslide, streams have carved deep cuts in the cliffs in Wailau and Pelekunu Valleys. Wind, rain, and wave erosion continue to chip away at the cliffs from literally every side. The cliffs themselves are still shifting today, as evidenced by a landslide near Pelekunu Valley in 1999 that caused an entire section of mountain to collapse and crash into the sea. These constant changes are powerful reminders that Molokai’s tropical scenery is always evolving – one day to the next.
The best way to experience the Molokai sea cliffs is by booking a private charter boat for a cruise of the northern coastline, or by hiking or mule riding your way down the cliffs on the trail to Kalaupapa. Interestingly, the entire Kalaupapa Peninsula didn’t exist at the time of the massive landslide, as it was formed from an entirely separate eruption about 300,000 years ago.