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Piti Guns

sketch of gun

On the morning of July 21, 1944, troops of the 3rd U.S. Marine Division landed on the beaches at Asan. At the same time U.S. troops landed to the south at Agat, near Ga'an Point. These landings marked the beginning of the recapture of Guam after 32 months of Japanese occupation during the second World War. The assault was a critical part of the Marianas Campaign, aimed at establishing a beachhead in the western Pacific. Saipan (to the north) fell to U.S. forces in July of 1944.

The landings on Guam were preceded by days of heavy air and naval bombardment from U.S. ships offshore. The Japanese, in preparation for the assault they knew was inevitable, heavily fortified the hills above these beaches. By the time the smoke had cleared and the island was declared secure on August 10, many of these fortifications had been damaged; time and weather have taken their toll on the rest. Among the more spectacular remains of the Japanese fortifications are three coastal defense guns in the hills above Piti.


trail map

Access to Piti Guns today is by way of a short (1/4 mile) but steep trail which begins in the village of Piti. Drive 2 miles west of the park visitor center on Marine Drive, and turn left onto J.M. Tuncap Street, across from Santos Park. Drive to the end of the street and turn right at the stop sign. Take the very next left onto Father Mel Street and park on the right under the monkey pod tree next to the church social hall (buses should use the church parking lot). The trailhead is just behind the wayside exhibit panel at the base of the hill.

The trail ascends steeply through thick coastal jungle, reminiscent of that negotiated by both Japanese and U.S. troops. Many of the large trees along the lower portion of the trail are African tulip (Spathodea campanulata). Their large orange-red flowers are hard to miss. Some of these trees are quite old (65 years or more); one of the largest is on the left, about halfway up the concrete steps. Note also the Chinese or betel nut palms (Veitchia merrilli). Prominent shrubs along the trail include croton (Codiaeum variegatum), with dark green variegated leaves, and hibiscus (Hibiscus). Spider lilies (Crinum asiaticum) grow in profusion on the forest floor, as do several different ferns.

The vegetation has changed somewhat since 1944. Thick stands of tangantangan (Leucaena) are now firmly established as a result of Navy efforts at revegetation in 1947. Tangantangan has been on the island for close to 100 years but has become particularly invasive in the last 50 years.

After a steep ascent to the first gun, one is rewarded with a view of Apra Harbor, the Orote Peninsula in the distance, and the village of Piti below. All were scenes of fierce fighting during the 1944 battle. During the pre-war years, Piti was a major rice-growing area. Very little of Piti survived the 1944 campaign.


These guns are Japanese-made Vickers-type Model 3 (1914) 140 mm (5.5 inch) coastal defense guns. Japanese foundry stamps are visible on the breech. The first two guns were sited in earth revetments; the third gun sits in a low-walled concrete emplacement. The guns had a range of close to 10 miles and were intended for use primarily against ships and landing craft.

Ironically, these three guns were never fired. The hasty efforts by the Japanese to complete fortification of the island were never completed, and these guns were not operational on the morning of July 21. They are typical, however, of large coastal defense guns used throughout the Pacific island campaigns during World War II. Please use caution here: do not climb on or otherwise disturb these historic remains.

The trail from the first gun continues along the left fork to the second coastal defense gun, partially buried in thick vegetation. This gun was dislodged from its base following the war. Continue along the trail just a few hundred yards to the third gun.



The third gun, located at the end of the Piti Guns Trail, occupies the most spectacular site. From this high ground the Japanese had a clear view of the beaches below. In the pre-war years, these beaches were covered with thick stands of coconut palms. By the morning of July 21, most of the vegetation had been destroyed by the heavy naval bombardment in the days prior to the landings.

The assault on Asan Beach on July 21 was made by members of the 3rd Marine Division. The area which included these fortifications was captured on July 22 by the 9th Marine Regiment.

The large tree with small lobate leaves which towers over the third gun is a Kamachile (Pithecellobium dulce). A native of central America, this tree was introduced to the Marianas from the Philippines.


Piti Guns is one of seven units of War in the Pacific National Historical Park. The park was established by Congress in 1978 "to commemorate the bravery and sacrifice of those participating in the campaigns of the Pacific theater of World War II, and to conserve and interpret outstanding natural, scenic and historic values and objects on the island of Guam for the benefit and enjoyment of present and future generations."

The recapture of Guam resulted in thousands of American and Japanese casualties. The exact number of Chamorro casualties will never be known. Fifty five thousand U.S. armed forces personnel were involved in the landings at Agat and Asan. It was from the Mariana islands that U.S. forces launched the final attack on Japan which ultimately ended the war.



The guns above Piti are located on the edge of a small forest of mahogany trees, planted around 1928. The fork in the trail at the 2nd gun takes you into the heart of this forest, although mahogany trees are scattered throughout the area. These trees are all that remain of the former Guam Agricultural Experiment Station (1909-1932) and agricultural school (1932-1940).

These are broad-leafed mahogany, Swietenia macrophylla, native to Central and South America. The largest of these trees, some distance off the trail, are up to 100 cm in diameter and 65 years old; a few may be older. Mahogany is grown for timber throughout the tropics and is valued for its hard wood and handsome grain.

Last Updated: 01-Apr-2004