A railway system that operates beneath the surface of a city, primarily designed for urban transportation and connecting various districts, often referred to as a metro or subway.
A transportation network consisting of trains that travel through underground tunnels to efficiently move people within densely populated urban areas, minimizing surface congestion.
A type of public transit that is specifically constructed underground, allowing for travel through the city without interfering with the above-ground environment, commonly used in major metropolitan areas.
Example:
地下鉄で行きたいのです。
A meticulously planned terrorist attack that occurred on the Tokyo subway system, involving the release of a deadly nerve agent, leaving numerous casualties and significant public panic.
An incident on March 20, 1995, where perpetrators deployed sarin gas in a crowded urban transit environment, resulting in a tragic loss of life and raising critical concerns about domestic terrorism in Japan.
A catastrophic event characterized by the intentional use of chemical warfare in a civilian setting, which profoundly impacted national security policies and public awareness regarding the threats posed by extremist groups.
A landmark case in Japan's history that highlighted vulnerabilities in urban safety and emergency response, stemming from the coordinated attack orchestrated by a doomsday cult on unsuspecting commuters.