Ahupua‘a are traditional land divisions. On older islands like O‘ahu and Kaua‘i, they were often defined by the watershed of a stream.
These ahupua‘a are pie-shaped because they follow the stream from the mountain headwaters to the coastal delta. Almost all of the resources needed to sustain a community were found within the boundaries of the ahupua‘a.
The boundaries of the ahupua‘a were marked with altars on top of which was the carved head of a pig (pua‘a), often made from kukui wood.
The younger lands of Kona are not shaped by streams. Rain falls onto the porous lava soils and runs off in sheets and quickly drains beneath the surface. In Kona, ahupua‘a are rectangular, not pie shaped, because they are not formed around streams.
There are about 600 ahupua‘a on the island of Hawai‘i. Where resources are scarce, the ahupua‘a are broad, up to 5 miles wide at the coast. Where resources are abundant, as they are in Kona, ahupua‘a are narrow, many less than a quarter mile wide.
Amy Greenwell Garden is in the ahupua‘a of Kealakekua. Kealakekua is often translated “pathway of the god.” The coastline of the ahupua‘a formed one side of the famous Kealakekua Bay. Above the bay were many productive farms and a large tract of upland forest. Many historical figures such as Kamehameha and his wife Ka‘ahumanu lived in this celebrated ahupua‘a.