The Matsushiro Underground Imperial Headquarters is a historical site located in Nagano Prefecture, Japan. Built during World War II, it served as a military command center for the Imperial Japanese Army. The facility consists of a network of tunnels and rooms carved into the mountainside, designed to protect officials from air raids. Today, the headquarters is a popular tourist attraction, offering guided tours that showcase its strategic importance and architectural features. Visitors can explore the underground passages and learn about the wartime activities that took place there, providing insight into Japan's military history during the conflict.