Video thumbnail for Behind Tokyo’s 2.8-mile flood-defense tunnel under the city

Behind Tokyo’s 2.8-mile flood-defense tunnel under the city

Oct 6, 2026

ZMG - Amaze Lab

There are a lot of ways humanity is readying itself for the effects of climate change, but in Japan, they’re digging. They are tunneling a massive 42-foot-wide cavern that will eventually stretch some 2.8 miles under the city of Tokyo and divert flood waters.
science