Kamakura is a city of tunnels. Surrounded by low mountains and cliffs, its citizens had to dig for convenience throughout its history. Most of its tunnels are officially named, and one of them recalls an unusual legend.

Nekonoike Tunnel, which provides a passage in a suburban neighborhood in West Kamakura, seems like nothing extraordinary. But its name is a connection to a local legend—it means "cat pond," named after a nearby pond that has been lost today.

While the tunnel is the only thing that keeps the memory of this pond alive, this name happens to have a folktale behind its origin. According to the local legend, the pond was home to a shapeshifting serpent, which took the form of a giant cat and surprised a farmer by giving him a shade. The snake-cat grinned at the startled farmer and disappeared, leaving behind a pond called "cat pond."