tunnel, n.Trivia

The distinctive nose of Japan's Shinkansen 500 Bullet Train prevents sonic booms whenever it exits a tunnel and was discovered when scientists studied the shape of a kingfisher's beak to learn how it hit the water at high speed.

Giant sloths excavated hundreds of miles of tunnels in South America that still exist to this day

Tunnels are among the safest place to be during earthquakes since they move with the soil while structures above ground sway back and forth