|Pseudonym reading||Tengu Mori no Tsutsuoriyamazanakana|
|Specified type||Prefecture designation|
|Type||Natural monuments and geological minerals|
|Designated date||February 15, 1974|
|location||Hachimantai City Tengu Forest National Forest|
The summer iceberg breeze of Tengu Mori in Hachimantai is located on the north slope of the ridge that extends east from Sanbon-dake at the border of Akita Prefecture, at an elevation of about 600 m.
The name comes from where ice can be seen even in summer.
There is a cliff where sediments of fine columnar joints of rhyolite collapse from the peak.
The cliff is approximately 50 m in length and 25 m in width at the lower part, and is fan-shaped and has 10 or more wind holes.
There is a deep gap in the rock formation that makes this cliff, and the cold air passes through this gap, so winter ice remains until summer.
It is not until September that the ice that has formed in the crevices of the rock completely melts.
In the windhole area, since cold air is present and the temperature is low, there are special plants called windhole plants such as Ezoguri-tan-bok, Komagatake-ri, Nambu-so and Ezo-meshida.
Although the scale is small as a windhole, it is valuable in terms of geology and plant distribution and is valuable.