[citation needed] The Kapampangan empire expanded their trade throughout Central Luzon, but were forced to create roads adjacent to the Pampanga River.

They widened the road, constructed wooden bridges, and connected it to Olongapo, a very vital location which enabled them to easily access Subic Bay, the site of their naval base.

At the aftermath of the disaster, these sections were rehabilitated, which involved building new roads and bridges and construction of an embankment which made their elevation become higher to withstand further lahar flows.

In recent years especially after lahars from Mount Pinatubo eruption buried some sections of the avenue, the highway underwent widening which added more lanes to accommodate more vehicles using the road.

The road passes to Gapan, San Isidro, and Cabiao in Nueva Ecija, Arayat, Santa Ana, Mexico, City of San Fernando, Bacolor, Guagua, and Lubao in Pampanga, Hermosa and Dinalupihan in Bataan, and finally to the city of Olongapo in Zambales.

It then passes through residential areas and institutions within the municipalities of Arayat, Santa Ana, and Mexico before entering San Fernando.

It continues straightforward, passing through residential areas and establishments within the municipality and parallels the Lubao Old National Road.

It then enters Bataan through the Pampanga Welcome marker and traverses the municipalities of Hermosa and Dinalupihan, where it turns right at the Layac Junction.

It then parallels into it, continues on a straight direction, passings through barangays San Benito, Colo, Naparing, Happy Valley, and Roosevelt National Park Protected Area, and the eastern end of Subic Freeport Expressway.

It enters Zambales a few meters after the said exit and continues on a zigzag pattern before passing through residential areas within Olongapo.

The road then enters the city proper of Olongapo, where it is locally known as Rizal Avenue, and continues towards National Highway (N306) at its terminus at the Ulo ng Apo Rotonda.

The Jose Abad Santos Avenue spans for about 118 kilometers (73 mi), thus, many establishments and landmarks are built alongside the highway.