Wikipedia
Yamabiko
The is a high-speed Shinkansen train service operated on the Tōhoku Shinkansen between and by East Japan Railway Company (JR East) in Japan.
Yamabiko (folklore)
The yamabiko is a mountain god, spirit, and yōkai in Japanese folklore.
The term "yamabiko" is also used to describe the phenomenon of a delayed echo in mountains and valleys, and is thought to be the spirit answering. In this case, it is written as 幽谷響. This anomaly is also sometimes called "kodama", when it is thought to be the answering voice of a tree spirit (木霊 or 木魂).