The rules on noise pollution are very restrictive in Japan, and in the case of the bullet train running to more than 350km/h, a very aerodynamic design was needed for the times it came out of the tunnels.

The ingenious solution of the shape of this high-speed train mimics the shape of the bluebird beak, who, when they immersed into water at great speeds, almost does not alter the tranquility of the water.