Following the attack on Pearl Harbor on Oahu on December 7, 1941, the military presence in Hawaii Territory was immediately bolstered. Although the main influx of military activity in Hawaii Territory was centered around Oahu there also was a military presence on Maui. During 1942 construction of Naval Air Station Kahului began and established many roads around the facility. It is likely that what is now Keolani Place was constructed as part of Naval Air Station Kahului.
Following the conclusion of World War II, Naval Air Station Kahului was turned over to the Hawaii Aeronautics Commission. The facility was converted to civilian usage and reopened during June 1952 as Kahului Airport. Haleakala Highway can be seen traversing the grounds east from Hana Highway through the grounds of Kahului Airport on the 1954 United States Geological Survey map of Paia.
The Island of Maui seemingly was not part of the original World War II era Hawaii Route System. Circa 1955 the United States Bureau of Public Roads renumbered the Hawaii Route System. The 1955 Hawaii Route Renumbering saw most of the conventions utilized by the current Hawaii State Route System established. Primary Hawaii Routes were given two-digit numbers whereas Secondary Hawaii Routes were given three-digit numbers. The Hawaii Routes were assigned in sequence for what Island/County they were located on coupled with what Federal Aid Program number they were tied to. In the case of the Island of Maui it was assigned numbers in the range of 30-40.
An information plaque at the Red Hill Summit House notes the depth of Maui extends 19,680 feet below the Pacific Ocean.