World War II History

throughout the island and both complexes. Digging by hand would have been slow going, and according to Peck (1984:20), the Japanese military used dynamite from the South Seas Development Company and explosives taken from unexploded American bombs to assist in tunnel construction. Peck (1984:20) also noted that existing natural caves were augmented and enhanced as recessed fortifications.

After interviewing Manual M. Ogo about his experiences of digging a Japanese military tunnel in Rota during the war, Peck (1986:7) wrote: The work was brutal and painful, for the tunnel was being hand-chiseled inch by inch through solid rock; and it demolished its workers in short order, for the coral dust suffocated them and brought on uncontrollable attacks of coughing and breathlessness. The heat in the tunnel was intolerable and the pressure for haste unrelenting.

Like Rota, the Japanese Imperial Army and Navy extensively used caves on Peleliu (Denfeld 1988:37-38,97-102). The cave/tunnel system on Peleliu was studied by the US military, providing a cave typology (Table 2). The caves are named by their shape corresponding to a letter of the alphabet. Additionally, different cave types were built by the Japanese Imperial Navy, the Japanese Imperial Army, or both, allowing for caves/tunnels on other islands to be identified and assigned to different branches of the Japanese military.

Who designed and built the caves – Imperial Japanese Army, Imperial Japanese Navy, conscripted local Chamorros – is not fixed. According to a 1983 study of the Ginalangan complex, the observed “caves conform to official Japanese Naval tunnel standards (of the Suidatai Unit) with ‘U’ shaped tunnels functioning as combat and shelter areas and ‘L’ shaped tunnels for housing generators, mortars, and 75 mm guns” (Peck 1984:24). The Navy design and building of the complexes is also supported by (Denfeld 1997 and Rottman 2002), who believe that the Navy’s 56th Guard Unit was heavily involved in building the island’s defenses. However, only 17 of the 66 caves in Gingalangan and Chudang Palii fit into one of the Peleliu cave typologies. Ten of the 17 are exclusively Army, while the remaining seven were styles built by both the Army and the Navy. The remaining 49 caves appear to fit none of the designs.

While some of the caves/tunnels in Chudang Palii were definitely constructed from whole cloth, many of the caves/tunnels appear more augmented than completely constructed as evidence by their not following any of the Imperial Japanese Navy or Army standardized cave designs. The lack of an apparent standardized design may 50 ・ Marianas History Conference 2012