Pearl Harbor Naval Shipyard and Intermediate 

Maintenance Facility 

Pearl Harbor, Hawaii 

Cultural Resources Fact Sheet 

Location 

Pearl Harbor Naval Shipyard & Intermediate Maintenance Facility (PHNSY & IMF) is located on Joint Base 

Pearl Harbor-Hickam on the southern shore of the Island 

of Oahu, Hawai‘i. PHNSY & IMF encompasses 148 acres 

and is located in the ahupua‘a of Hālawa in the moku of 

‘Ewa. Pearl Harbor itself, or Pu‘uloa, consists of about 36 

miles of shoreline divided into three distinct lochs that 

share a narrow outlet. PHNSY & IMF is located on the 

shore of East Loch near Ford Island and the Pearl Harbor 

National Memorial. 

Mission 

Located on the island of O`ahu, Hawaii, PHNSY & IMF’s 

strategic location is a vital waypoint and defensive outpost between the U.S. mainland and the rest of the AsiaPacific region. As the largest industrial employer in Hawaii, with approximately 5,800 civilian employees and 

500 active duty military personnel, PHNSY & IMF’s mission supports the maintenance and modernization of the 

U.S. Pacific Fleet. PHNSY & IMF currently supports Los 

Angeles-class submarines and is looking to the future 

and bringing on more modern lines of submarines. For 

the foreseeable future, PHNSY & IMF’s nuclear maintenance workload will remain steady or increase. 

Pearl Harbor Naval Shipyard & IMF — Cultural Resources Fact Sheets pg. 1 

History 

The archaeological record indicates that Pearl Harbor 

was a favorable location for traditional Hawaiian aquaculture. A total of 27 fishponds have been documented in 

Pearl Harbor. The shipyard was known from historic 

maps to be the site of three traditional Hawaiian fishponds, including Loko Pohaku, Loko Amana, and an unnamed fishpond. Based on radiocarbon dates and traditional accounts, these fishponds were initially constructed 

during the fourteenth century, and used through the sixteenth to eighteenth centuries. However, these 

former fishponds have been filled at least since 1919, 

as the location was used for industrial activities associated with the shipyard. 

Pearl Harbor became an active naval facility in the late1880s when King Kalākaua granted the U.S. exclusive 

rights to enter Pearl Harbor and establish a coaling and 

repair station. In 1908, the U.S. Congress established 

Pearl Harbor Navy Yard, Territory of Hawaii and authorized $3 million to build it. Over the next 11 years, Pearl 

Harbor channels and lochs were enlarged and dredged, 

shops and supply houses constructed, and Dry Dock No. 

1 opened. In the mid-1930s, further efforts were made to 

improve the entrance channel and build repair facilities 

that would make Pearl Harbor a major overhaul base with 

capabilities equal to those at Mare Island (closed 1996) 

and Puget Sound naval shipyards. By May of 1940, Pearl 

Figure 1. Present-Day View of the Pearl Harbor Naval Shipyard 
Pearl Harbor Naval Shipyard & IMF — Cultural Resources Fact Sheets pg. 2 

 Pearl Harbor Naval Shipyard & IMF Cultural Resources Fact Sheet

Harbor Navy Yard had a dry dock capable of holding the 

largest warships, a marine railway for smaller ones, an 

industrial plant for repairing and maintaining these ships, 

numerous support facilities, and abundant mooring and 

docking locations for ships, including a berthing area 

along the eastern side of Ford Island that was commonly 

called “Battleship Row.” During 1940-1941, construction 

of new facilities was undertaken at a rapid pace including 

new permanent dry docks and expansion of the supply 

depot. President Franklin D. Roosevelt transferred the 

U.S. Fleet to Pearl Harbor as a presumed deterrent to 

Japanese aggression in the Pacific, but 18 months later, 

on December 7, 1941, the forces of the Imperial Navy of 

Japan targeted Pearl Harbor and thrust America into 

World War II. Twenty-one ships were damaged and/or 

sunk in the attack and over 2400 Americans killed. Pearl 

Harbor Navy Yard provided pivotal support during the 

war effort and significantly contributed to the hard-fought 

victory in World War II. 

After the war, the official name of the facility was 

changed to Pearl Harbor Naval Shipyard. While there 

was little new construction in the decades following the 

war, the shipyard continued to support the Fleet in major 

U.S. military operations including the Korean Conflict, the 

Vietnam War, and the Cold War. During the Korean Conflict, the shipyard provided ship repairs and prepared 

mothballed ships for active service. In 1959, the shipyard 

was designated as the planning shipyard for Regulus 

and Permit class submarines and also began performing 

Fleet Rehabilitation and Modernization (FRAM) work on 

both submarines and destroyers in an effort to extend 

the life of the ships. Throughout the Cold War, Pearl Harbor Naval Shipyard provided support for a variety of Navy programs that enhanced and upgraded vessels with 

the latest technological advancements. PHNSY and the 

IMF were consolidated in 1998 to capitalize on the combined capabilities of the two elements. 

Historic Properties 

The U.S. Naval Base, Pearl Harbor was listed as a National Historic Landmark (NHL) in 1964. The nomination 

and boundaries were revised and amended in 1974 and 

again in 1978. The NHL encompasses PHNSY & IMF 

and the surrounding water, land, and facilities. The NHL 

was determined to have significance under Criteria A and 

C in the areas of military, engineering, and industry. 

There are other properties listed as NHLs, or individually 

listed in the National Register of Historic Places (NRHP) 

within the vicinity of PHNSY & IMF. There may be additional NRHP-eligible properties within and in the vicinity of 

PHNSY & IMF. 

Figure 3. Pearl Harbor Dry Dock, 1919

Figure 2. Pearl Harbor Naval Shipyard, 1941