The War in the Pacific National Historical Park is a unit of the United States National Park System located on the island of Guam. It was established by an act of Congress in 1978 to commemorate the bravery, sacrifice, and loss of those who participated in the Pacific Theater of World War II. The park preserves and interprets key historic sites and natural resources associated with the 1944 liberation of Guam by American forces, a pivotal campaign in the Allied advance toward Japan.

The park is not a single contiguous area but is composed of seven distinct units scattered across the central and southern parts of the island. These units encompass former battlefields, gun emplacements, trenches, caves, and landing beaches. Key sites include the Asan Beach Unit, which was a primary landing area for U.S. Marines, and the Agat Beach Unit, where U.S. Army forces came ashore. The Fonte Plateau Unit preserves high ground that was fiercely contested during the battle.

Beyond its military history, the park protects significant ecological and cultural resources. The coastal areas include limestone forests, coral reefs, and seagrass beds that are home to diverse native species. The park's landscapes also contain remnants of the ancient CHamoru culture, including latte stone sites, which are stone pillars used as foundations for traditional houses. This integration of natural and cultural history provides a broader context for understanding the island's story.

The park's visitor center, located in the Asan Bay Overlook unit, serves as the primary orientation point. It houses museum exhibits featuring historical photographs, artifacts, maps, and personal accounts that detail the events of the war in the Pacific, the Japanese occupation of Guam, and the subsequent liberation. An outdoor memorial wall at the overlook honors the CHamoru people who suffered during the occupation and lists the names of U.S. servicemen who died during the recapture of the island.

Educational and commemorative programs are central to the park's mission. Rangers conduct guided tours, living history demonstrations, and lectures. The park also hosts annual memorial ceremonies on significant dates, such as Liberation Day on July 21st, which marks the return of U.S. forces to Guam. These activities ensure that the lessons and legacy of this critical period in world history are passed on to future generations.