West Maui Mountains

The West Maui Mountains, West Maui Volcano, or Mauna Kahālāwai (which means "holding house of water") are the remnants of an eroded shield volcano that constitutes the western quarter of Maui. Approximately 1.7 million years old, the volcano's last eruption was approximately 320,000 years ago. Thanks to hundreds of inches of rainfall annually the mountains have undergone substantial stream erosion. The ʻĪao Valley, and it's Iao Needle are popular attractions within mountains, is accessible from Wailuku.

The three districts (moku) of West Maui are Lahaina, Kāanapali, and Wailuku. Wailuku is also known as "Pūalikomohana" ("west isthmus"), or "Nā Wai Ehā" ("the four waters"). The port of Lahaina lies on the southwestern slope.

The summit peak at 5788 ft elevation is called "Puu Kukui," which translates to "candlenut hill".

Geological history
The West Maui Mountains were formed through at least three series of major volcanic eruptions during its shield building period. Rocks from the latest major shield-building eruptions are called the Honolua volcanic series, which are roughly 500,000 years old. However, there were several rejuvenated stage eruptions more recently, the last dating to roughly 320,000 years ago.

Puu Kukui Watershed Preserve
The Puu Kukui Preserve is the largest private nature preserve in the State of Hawaii, dedicated to protecting the watershed lands of the West Maui Mountains. Established in 1988, the 8661 acre preserve has been managed since 1994 by Maui Land & Pineapple Company in participation with The Nature Conservancy and the State Natural Area Partnership.