The island of Maui is composed of two separate major volcanoes. East Maui comes topped by 10,023-foot Haleakala, which is still active. The West Maui shield volcano, meanwhile, had its heyday more than a million years ago. Hundreds of thousands of years of stream-cutting, landsliding, and other erosion processes have carved the old shield into the exceedingly rugged—and utterly gorgeous—West Maui Mountains.
Separated from Haleakala and East Maui by the island’s central isthmus, the West Maui Mountains are also known as Mauna Kahalawai. They top out on 5,788-foot Puu Kukui, though in its early, active days back in the Pleistocene, the West Maui shield volcano likely approached 11,000 feet high.
As cool as active lava lakes and fountains are, we can be thankful for the old, retired status of the West Maui shield volcano. Without fresh lava flows countering them, the forces of erosion have sculpted incredible terrain. Knife-edged ridges and steep-sided gorges and valleys display Maui at its ruggedest.
The northern and eastern flanks of the West Maui Mountains—their windward aspect—are especially rain-clobbered. All that cutting stream power, steep topography, and abundant rainfall makes for a multitude of waterfalls, both permanent and ephemeral.
Deep-walled valleys such as the Waihee and Honokohau are jaw-dropping. But the greatest chasm in the West Maui Mountains is the east-running Iao Valley. With a headwall that includes Puu Kukui, the Iao partly represents the former caldera of the West Maui shield volcano, broadened and extended by erosion and weathering.
Some of Valley Isle’s best hiking trails lie within the West Maui Mountains. On the northeast side, the Waihee Ridge Trail shows off the lush, windward splendor of the range. You’ll enjoy stunning vistas of landmarks such as Makamakaole Falls and the flat-topped peak of Mount Eke, the site of a high-elevation bog.
Contrast all that lushness with the Lahaina Pali Trail, which crosses the semi-arid leeward southern slope of the West Maui Mountains. It’s hard to believe that brown, barren, gully-ridden flank is part of the same mountain mass.
The trail into the Iao Valley to the Iao Needle is maybe the signature hike in the West Maui Mountains. Deeply sacred to Native Hawaiians, the Iao Valley is one of the most beautiful spots in all the Hawaiian Islands. The famous Iao Needle—which looks like a spire head-on, hence the name, but is actually a razor-thin ridge—is an outcrop of Wailuku Basalt. (That’s the oldest of three major geologic formations composing West Maui, the younger layers being the Honolua and Lahaina volcanic.)
More than 9,000 acres of the West Maui Mountains fall within Hawaii’s largest private nature reserve, the Puu Kukui Watershed Preserve. This was established by the Maui Land & Pineapple Company. A boardwalk through its dripping rainforest and montane bogs provide another unforgettable West Maui hike.
Another popular way to see the West Maui Mountains is from the air. Multiple tour companies offer helicopter sightseeing flights over the range, which is the best way to see its waterfalls and get a big-picture sense of the terrain.
Lower as they may be than Haleakala to the east, the West Maui Mountains very much hold their own in the scenery department. Spectacular as the West Maui coastline is—and you can definitely get nice mountain views from it—you’ll be rewarded for trekking into the interior!
Whether hiking or booking a helicopter flight, keep in mind that mornings are likeliest for clear views in the West Maui Mountains. Clouds tend to wrap these green heights by afternoon. That said, the thick mists—lifting here and there to briefly expose a ridge or peak—create their own evocative scenery.