During World War II, the Yuma proving ground of the United States Army Corps of Engineers was known as the Yuma Test Branch and was used as a floating-bridge test facility. By 1944, more allied troop support was needed to conduct bridge tests there. After Italy had surrendered to the United States, a group of Italian prisoners of war captured in North Africa pledged their loyalty and support to the United States. These Italians were formed into two Italian service units and were stationed at the Yuma Test Branch from 1944 to 1945 to assist in testing floating bridges. In addition to their bridge-building capability, they were talented in fine art, culinary art, and stonemasonry. They constructed a concrete-lined, stone-faced paint shed decorated with three castles bearing the United States Army Corps of Engineers insignia and one castle inscribed with the word "Italy" to facilitate the safe storage of paint at the Yuma Test Branch. Because the temperature was cooler underground, the paint was stored below ground under the stone decorations, a method free of fire hazards.