Ahupua'a O Kahana State Park, State park in Honolulu County, Oahu, Hawaii, United States.

Ahupuaʻa O Kahana State Park is Hawaii's only public ahupuaʻa, a land division running from Kahana Bay mauka (uphill) to the 2,670-foot summit of Puʻu Pauao. The valley rises through lowland koa, hala and pasture into wetter slopes of mountain apple, strawberry guava, ti and bamboo. Streams crossed by the Nakoa Trail hold ʻoʻopu naniha, and the Huilua Fishpond lies near the shore.

The valley was a settled center before Western arrival, where people fished and cultivated taro in fertile soil while using mountain springs for fresh water. The site was later protected as a state park to preserve this traditional land-use system.

The name comes from the Hawaiian concept of ahupua'a, which represents the connection between mountains and the sea and how communities once managed water and resources together. Visitors can observe how this approach still shapes how the land is cared for today.

Visitors can explore two different walking trails that pass through various landscape types and offer different levels of physical challenge. It is important to come prepared for tropical weather, especially during wetter months, and wear sturdy footwear.

Some areas receive so much rainfall that they rank among the wettest spots on the island, which explains why vegetation here grows so thick and green. This extreme abundance of water shapes the entire ecosystem and the hiking experience.