Daidarabotchi

Daidarabotchi (ダイダラボッチ, 大座法師) was a gigantic type of yōkai in Japanese mythology, sometimes said to pose as a mountain range when sleeping.

Mythology
The size of a Daidarabotchi was so great that his footprints were said to have created innumerable lakes and ponds. In one legend, a Daidarabotchi weighed Mount Fuji and Mount Tsukuba to see which was heavier, but he accidentally split Tsukuba's peak after he was finished with it.

The Hitachi no Kuni Fudoki, a recording of the imperial customs in the Hitachi Province compiled in the 8th century, also told of a Daidarabotchi living on a hill west of a post office of Hiratsu Ogushi who fed on giant clams from the beach, piling the shells on top of a hill. In the larger Ibaraki Prefecture, Daidarabotchi was considered a benevolent giant, moving mountains to aid the people of Ibaraki. In Mito, Ibaraki, a 15-meter statue was erected in Ogushi Kaizuka Park to commemorate the yōkai and its myths.

Izumo no Kuni Fudoki also mentions a legendary king of Izumo, Ōmitsunu, who was the grandson of Susanoo and a demi-god. Having the strength of a giant, he performed Kuni-biki, pulling land from Silla with ropes, to increase the size of his territory.

The Daidarabotchi was also said to reside at Mount Togakushi, where there exists a pond on its south side bearing its name.