Xiyu Ammunition Depot Introduction
We often use the term "copper wall and iron wall" to describe the sturdiness of a house, but the Western Islet Ammunition Depot is a true example of a "copper wall and iron wall"! The Western Islet Ammunition Depot includes an underground cooling ammunition storage and a cave-style ammunition storage known as the "copper wall and iron wall." It is a rare military structure from the early Japanese occupation and one of the four major ammunition depots established by the Japanese army on Penghu Island. The Western Islet Ammunition Depot, as the name suggests, is mainly used for storing artillery ammunition. The cave-style ammunition storage comes in two types: single-cave and double-cave, which store two kinds of gunpowder—smoky and smokeless—respectively. The cave ammunition storage uses a double-walled dome structure; a round arch cave is excavated on the rocky bed of the mountain, which is then piled with concrete blocks to form the outer storage structure, while the inner storage space is constructed with reinforced concrete. To store smokeless powder, it maintains constant temperature and humidity, and the side walls are lined with copper sheets to completely isolate electromagnetic pulses and moisture. On the other hand, the underground cooling ammunition storage is an above-ground construction with stone walls, wooden interior walls, and raised wooden flooring for moisture prevention. The roof framework is made of steel trusses, and the roof tiles are made of cultural tiles, also known as blackened tiles. A lightning rod is installed on the roof to prevent lightning strikes. These two types of ammunition depots are rare military buildings from the early Japanese occupation in Taiwan, showcasing the characteristics of construction techniques during that period, and have been designated as county-registered historical sites for restoration and preservation.
