The Kapālama Ahupua'a stretches from the coast to the head of Kapālama Gulch, approximately 4 kilometers inland. Unlike other leeward ahupua'a on O'ahu, Kapālama does not extend all the way to the Ko'olau Mountains, as it is bordered by Kalihi Ahupua'a on the west and Nu'uanu Ahupua'a on the east.

The highest peak in Kapālama is Nāpu'umai'a, also known as Pāka'aluna, situated at 1870 feet above mean sea level in the western section of Nu'uanu's Waolani Valley. Waolani, which means "heavenly mountain area," also refers to a peak on the ridge that separates Kapālama from Nu'uanu's Waolani Valley. The boundary with Nu'uanu extends along the western edge of 'Ālewa Heights and descends to the coast, passing through the rocky area known as Kalaepōhaku ("the stone promontory"). The exact lower eastern boundary of Kapālama is uncertain due to the development of Honolulu town, but on one early map, it extends as far as Nu'uanu Stream and includes the 'ili (smaller land divisions) of Kūwili and Iwilei, as well as the ponds Kūwili I and Kawa.

Keanakamanō, meaning "the cave of the shark," is both the name of a peak and a narrow valley on the western side of Kapālama. There is mention of a cave called Keanakamanō, but its precise location remains unknown. The western boundary of Kapālama, at the level coastal flats, runs from the mouth of Keanakamanō Valley along a low cliff separating Kapālama from the 'ili of Mokauea in Kalihi. This boundary is aligned with Waiakamilo Street and Houghtailing Street. The coastal boundary point is the eastern edge of Ananoho Pond in Kalihi.

Two streams, Kapālama and Niuhelewai ("coconut going [in] water"), converge and flow through the central fertile fields, also known as Niuhelewai. These fields drain into a pond called Kūwili II. There were two other named ponds, Kealia and Kapukui, situated east of Kūwili II. These ponds are depicted as part of Kapālama or Iwilei, depending on the map. The offshore waters were divided into the Iwilei, Kūwili, Kapālama, and Mokauea Fisheries, extending from the shore to the Koholaloa Reef. Several islands, including Mokauea Island off Kalihi and Koholaloa off Kapālama, were visible above this reef during low tide. Over time, the reef area was dredged, and the material was used to connect and expand small islands, ultimately forming Quarantine Island and Sand Island. The transformation of these names is further discussed in the section on "Changes in Honolulu Harbor."

Historical records suggest the existence of four ceremonial structures in Kapālama. Puea, a shrine, and three heiau (temples) named Pāka'aluna, Oomaunahele, and Paepaenuileimoku. While Pāka'aluna Heiau might have been located on or near Pāka'aluna Peak, the precise locations of the other three features are unknown, as are their meanings.

Kapalma: 
name of a well-known place nearby (the enclosure was constructed of lama-wood)
reserved solely for the unions of the highest-ranking chiefs.
higher ranked children, perhaps of ni'aupio rank or position, as a result.

"Ka ua koʻi-lipilipi o Kalihi."
There exists a tale called "Ka Ua Poʻolipilipi-o-Kalihi" that recounts the rain which sharpened heads. In ancient times, there were two lovers who sought seclusion in the forest to indulge in their love away from the prying eyes of the girl's parents. While they were there, a gentle rain began to fall, but they paid it no mind. Time passed, and they decided to check if the rain had ceased, only to find it still pouring down. They returned to their slumber. The rain persisted, falling continuously for several days and nights while the two lovers slept on. When they finally awoke, they discovered that their heads had become sharpened and flattened due to their extended sleep under the unrelenting rain. Henceforth, the rain in Kalihi came to be known as "the rain that sharpens the head at Kalihi," or "Ka ua Poʻolipilipi-o-Kalihi" (as cited by Poepoe in Sterling's account).
Haupe'epe'e
Nu'uanu: Makalaukoa, Puahiohio,and Malailua
Honolulu:
Ka ua Kukalahale o Honolulu.
The Kukalahale rain for Honolulu.
The rain that announces itself to the homes by the pattering it makes on the roofs as it falls. Often mentioned in songs.
‘Olelo No‘eau #1575