War in the Pacific
Cultural Resources Inventory
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Analysis and Evaluation

Seven landscape characteristics assessed for this report have retained high degrees of integrity and contribute to the historic character of the landscape. Archeology, buildings and structures, cluster arrangement, natural systems and features, spatial organization, topography, and views and vistas all played an important role in the historic events and remain in context on the landscape.

The defense structures in the archeology section fall into the category of archeological sites and are considered significant and contribute to the historic scene of the War in the Pacific National Historical Park.

The predominant buildings and structures found at the War in the Pacific National Historical Park are Japanese defense structures. These structures played a significant role in the history of the U.S. Military effort to recapture Guam. Since the 1940s, these structures have undergone weathering, however, they have retained integrity and are considered significant and contribute to the historic scene.

The cluster arrangement of Japanese defense positions retains integrity and is contributing to the historic scene of the War in the Pacific National Historical Park.

Natural systems and features played a significant role during the U.S. Military effort in Guam. Most notable, within the two beach units are five coral outcrops. Adelup Point and Asan Point flank both sides of Asan Beach, and Apaca and Bangi points flank Agat Beach with Ga'an Point located centrally in Agat Beach Unit. The Japanese focused on the enhancements of the natural caves and crevices. Defensive pillboxes, bunkers, and gun emplacements were clustered within these outcroppings and became strongholds for the Japanese defense. The spatial organization, of the historic and existing landscape, shows a clustering and clear relationship between the buildings and structures and the natural topography. Vegetation within both beach units has also contributes to the historic integrity. The five coral outcroppings retain the patches of limestone forests that hid Japanese defense structures from aerial and ground reconnaissance. These structures then became strongholds and impacted offensive landing and maneuvers. Coconut groves along the beaches have changed in regards to their densities and no longer retain integrity.

The spatial organization of the Asan and Agat battlefields were most influenced by the natural terrain. Both the offensive and defensive military strategies were planned around the existing landscape and the five limestone outcrops on Asan and Agat beaches. The spatial relationship between the coral reefs, beaches and coastal plains and the organization of the U.S. and Japanese military strategies that influenced the outcome of the recapture of Guam is still intact and contributing to the historic scene. The spatial relationship of the Japanese defense structures in the five coral outcroppings (Adelup, Asan, Apaca, Ga'an and Bangi points) are also still intact and contribute to the historic scene of the War in the Pacific National Historical Park.

Topography played a crucial role in the American offensive and Japanese defensive strategy. Changes to the topography since the period of significance have been minimal. As a result, topography in Asan and Agat beach units continues to remain significant and contributing to the historic scene of the War in the Pacific National Historical Park.

The historically significant views that were crucial in the military strategy and actual battle were longrange views from the sea and beaches toward high ground and vice-versa, short-range views from the sea toward the beaches and vice-versa, and short-range views in between the five points (Adelup, Asan, Apaca, Ga'an and Bangi). These views influenced the location of communication stations, gun emplacements, and other military strategies. Today, these views are still clear and contribute to the historic integrity of the War in the Pacific National Historical Park.

The seven characteristics that retain a high degree of historic integrity and contribute to the historic significance of Asan and Agat invasion beaches are archeology, buildings and structures, cluster arrangement, natural systems and features, spatial organization, topography, and views and vistas. All of these characteristics have played a significant role in and contribute to the historic events of the War in the Pacific National Historical Park.

Landscape Characteristics And Features

Archeological Sites

The arrival of the first inhabitants of the Mariana Islands occurred about 3,000 years ago, as documented by archaeological excavations in Saipan. Present evidence does not support prehistoric occupation of Guam prior to about 2,500 to 3,000 years ago (Olmo 1995:13).

Guam's prehistoric record is divided into two broad periods spanning the beginning of human settlement in the Mariana Islands (ca.1000 B.C. through European contact in A.D. 1521) the Pre-Latte and the Latte. The Latte period began ca. A.D. 800. Latte refers to stone columns found at many prehistoric living sites. They are hand hewn from nearby sources of coral, limestone, and volcanic rock. The columns are composed of two parts, an upright shaft and a hemispherical cap. They are usually found in groups, occurring in parallel rows, and are believed to be foundations for the floor beams of wooden houses. These houses most likely were those of high status individuals of the community (Olmo 1995:14-15).

The Latte sites were for permanent habitation (as opposed to temporary habitation sites associated with the northern limestone forests of Guam). Desirable features included fertile soils for agriculture, and productive reef-lagoon habitats for fishing (Hunter-Anderson 1989:7). The Agat coastal area of Guam was characterized as having geographic attributes that offered desirable habitation sites during the Latte period.

Pre-Latte sites indicate that the population, during initial phase of immigration and settlement, was located along coastal areas. The Hunter-Anderson study, done for the Small Boat Harbor at Agat, found no surface evidence of cultural remains. However, auger tests performed by Watanabe in 1986 indicated that pre-Latte subsurface remains might be yielded at Agat Beach. The "coral and sand beach overlie a substantial older intact alluvial clay deposit with localized evidence of prehistoric/early historic cultural remains" (Watanabe 1986:2). These remains may be non-residential but is a new site-type offering a model of prehistoric farming on Guam. The site may also offer recognition of a major geological event, during prehistoric human occupation on Guam, which caused the massive erosion evident in the deep alluvium at the Agat Beach study site (Hunter-Anderson 1989:27). The Small Boat Harbor study area is just south of the southernmost park boundary at Bangi Point. Although it is not within the boundaries, similar subsurface features are possible, if not probable, within the Agat Beach Unit.

Guam's historic period can be divided into four occupational periods The Spanish Period (A.D. 1664-1898), the First American Period (1898-1941), the Japanese Occupation (1941-1944), and the Second American Period (1944).

The Spanish Colonization period was well documented by Spanish government and military representatives, missionaries, and expeditionaries (Olmo 1995:16). Little material remains are present from the 234 years of Spanish occupation (Reed 1952:101). Many journals and written sources indicate that missionary efforts and Spanish settlement from 1668 mostly centered on Agana. However, the normal processes of time and vegetation growth along with the effects of typhoons and earthquakes have taken their toll on physical remains. But most destructive was the pre-bombing and battle of 1944. Archeological research identifies ruins of stone bridges and cathedrals to the north and south of NPS boundaries. No surface features from this period remain within Asan or Agat beach units. No sub-surface studies have been conducted within Asan or Agat beach units.

The First American Period spans 43 years, from 1898, when America acquired Guam as part of the settlement after the Spanish American War, until 1941 when the Japanese invaded. During this period, improvements to infrastructure included better roads, new schools and expansion of the water system (Olmo 1995:17). The Asan Beach Unit land use varied from detention camps to a Navy hospital throughout the 43 years. The Japanese destroyed many American buildings after taking control of the island in 1941.

During the Japanese occupation of Guam, little structural improvements were made. During the prebombing and battle of July 21 — August 10, 1944, any remaining structures within the Asan or Agat beach units were destroyed. Today, the beach units of Asan and Agat contain only Japanese defense structures. These include gun positions, bunkers, caves, and an offshore latrine (Olmo 1995:75).

Archeological studies have been done for Mt. Chachao (Olmo 1983), the Small Boat Harbor, Agat, (Hunter-Anderson 1989) and overviews of Guam (Reed 1952). Surveys done through the 1950s have focused primarily on the Pre-Latte and Latte Periods. Although no specific archeological studies have been done on Asan or Agat beach units, archeological investigations could yield subsurface information from WWII, prewar, Spanish, Latte, and Pre-Latte periods.

Defense Structures

When war looked imminent, the Japanese realized that they needed to plan a strategy and build defense structures. The decision to reinforce their position on the island had come so late (March 1944) that they had less than three months to prepare. General Takashina and his subordinates felt that between the lack of Japanese troops available, and the limited time period given to them for preparation, their situation was hopeless. Nevertheless, they began to build with the forced labor of the Chamorro people. There were critical shortages of cement, reinforcing steel, lumber, and a wide range of needed hardware, which limited the kinds of fortification that could be built (Gailey 1988:40). The defense structures included pillboxes, cave bunkers, tunnels, and gun emplacements. These structures varied from well-built concrete faced enclosures with multiple gun openings to crude and hurried concrete caps on holes dug in the dirt. However, some of these defense structures have lost integrity and are now contributing as archeological sites. These site numbers are 061, 062, 063, 064, 98, 102, 116, 032, 033, 023, 024 and 9 (see classified structure map).

Japanese Emplacement (LCS 061)
This reinforced concrete structure has one front wall embrasure and two side firing ports. The concrete extends back 7-feet into the west side of Asan Point. It takes advantage of a natural crevice between free standing boulders and the cliff wall to hide the entry. The field of fire was towards Cabre Island.

Japanese Emplacement (LCS 062)
This rectangular-shaped structure has a combination rock and concrete front wall and roof that enclose a natural crevice. The crevice extends into the cliff from the back of the enclosure. There is a 5' diameter steel gun base behind the front concrete wall.

Asan Point Japanese Gun Emplacement (LCS 064)
This pillbox is built into the western rock cliff of Asan Point with low angled concrete walls around the front opening. A metal gun base, possibly for a 20 centimeter coastal gun, is mounted into the concrete floor behind the front wall. The rear portion extends into two caves and a third cave is accessible from a side trench.

Asan Point Japanese Defensive Ridge Line (LCS 98)
Structure was not located after Supertyphoon Paka in 1998 or during 2000 List of Classified Structures (LCS) fieldwork.

Asan Beach, Offshore Japanese Pillbox (LCS 102)
Reinforced concrete pillbox is overturned and located approximately 40-feet offshore of Asan Beach. It has one embrasure and one rifle slit. It is not clear if the structure was initially located offshore and then overturned, or it was originally sited on the beach and later discarded offshore. No foundation site is apparent on the beach.

Double Gun Emplacements on Asan Ridge (LCS 116)
Two concrete structures are set into hill with only 2-3 feet openings above ground. These structures served as either fire control station or rifle/gun emplacements, one overlooking Piti, the other Asan Beach.

Adelup Point Cave and Foxhole (LCS 032)
This Japanese defensive structure built into the coral outcropping known as Adelup Point within the Asan Beach Unit.

Chorrito Cliff Seawall along Asan Beach (LCS 033)
This rock and concrete wall was once 400' long and is now only 75-feet long. It is a concrete wall atop a stonewall base. It is 40-inches high and L-shaped. The stone base was a remnant feature of the Spanish occupation (1800-1900) that was modified by the U.S. Military. It was intended to protect the new highway, built in 1944, against storm damage. Because it is now less than a quarter of its original length and broken in two places, it does not retain structural integrity. However, it is an important feature from the historic period and does contribute to the character of the cultural landscape. This feature is located on property owned by the Government of Guam.

Ga'an Point Japanese Bunker (LCS 024)
Located near Ga'an Point, this reinforced concrete pillbox is L-shaped and built between two rock escarpments. A smaller observation pillbox is located on the escarpent above with a connecting metal communication tube.

Ga'an Point Bunker (LCS 023)
This rectangular reinforced concrete pillbox is built into a limestone escarpment. It housed a 75mm 94 type gun with a field of fired over Agat Beach that caused havoc on U.S. Marines and landing craft on WDay until American troops captured it.

Ga'an Point Japanese Bunker (LCS 9)
This Japanese defense structure housed a 75mm gun with a field of fire directed across Agat Beach. The 20" thick walls are made of reinforced concrete and the structure has an irregular L-shaped plan.


Considering the location of pre-Latte habitation sites along coastal areas, and the subsequent history of Spanish, Japanese, and American occupation, it can be assumed that Asan and Agat beach units would likely yield subsurface archeological information. Defense structures are contibuting as archeological sites and are considered significant to the historic scene at the War in the Pacific National Historical Park.

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Last Updated: 03-may-2004