The hidden underground shrine in Tokyo you never knew about, guarding the city

By MOOK Scenic Spots Home Travel Life Network Editorial Department, compiled and reported by Liao Qiyu

No one would have imagined that amidst Tokyo’s developed architecture, there lies a mysterious and serene underground space, where over fifty massive pillars stand in orderly rows. Standing quietly beside these pillars highlights both the vastness of the space and your own insignificance, creating an otherworldly underground shrine reminiscent of a movie scene that sparks endless curiosity.

This “underground shrine” is actually the “Metropolitan Area Outer Underground Discharge Channel,” an underground drainage system hidden beneath Saitama Prefecture in Tokyo. To manage Tokyo’s high-density population, the Japanese government constructed this world-class drainage system deep underground at a depth of50meters. Centered around five water storage silos as tall as eight-story buildings—resembling colossal cans—the Japanese refer to this place as the “underground shrine” because these five enormous structures are supported by fifty-nine concrete pillars, each weighing500tons. Standing upright like soldiers in the underground space, they create a solemn scene reminiscent of an ancient Greek temple. This has made the underground shrine a famous tourist attraction, as well as a popular filming location for movies and commercials. During the rainy season, the main floodwaters from the capital region’s major rivers are collected through these five massive silos, then discharged via the Edogawa River, protecting the capital area from flooding. Additionally, the silos can also serve as underground reservoirs when needed. Their remarkable regulatory function is truly astounding.