Koolau

Koolau, commonly written Ko‘olau, refers to the Ko‘olau Range, a prominent mountain range on the eastern side of the Hawaiian island of O‘ahu. The range forms the island’s windward boundary, running roughly from Makapu‘u Point in the southeast toward Kahuku in the northeast.

Geology and landscape: The Ko‘olau Range is the eastern remnant of O‘ahu’s volcanic backbone, formed by ancient volcanic activity and later shaped by erosion and landslides. The range is known for rugged ridges, steep pali (cliffs), and deep valleys carved by rainfall-fed streams. The windward slopes receive substantial rainfall, supporting lush tropical rainforest and a range of microclimates along its height and exposure.

Ecology and conservation: Much of the range’s interior is forested and protected within state parks, reserves, and conservation areas. The habitat supports native and introduced plant and animal species, with ongoing efforts to manage invasive species, protect watershed areas, and maintain trails and visitor access.

Notable features and access: The Nu‘uanu Pali Lookout and the Pali Highway traverse the range, offering landmark viewpoints and access between Honolulu’s coastal areas and the windward towns of Kailua and Kaneohe. Mount Olomana, a popular hiking destination with a three-peaked ridgeline, sits on the range’s eastern side and exemplifies the dramatic terrain found throughout Ko‘olau.

Cultural significance: The Ko‘olau Range has long featured in Hawaiian history and culture. The Nu‘uanu region is linked to historic events such as the 1795 battle that contributed to the unification of the Hawaiian Islands, and the landscape has shaped settlement patterns, legends, and traditional land use on O‘ahu.