Reposted from description on youtube:

Kanboshi(Drying the coldest) Daikon (White Radish) is made in Hida Kamioka (The next town of Takayama) the Yamonomura area as a preserved food for winter. Peeled, sliced radishes are boiled and then hung out under the eaves for about a month to expose them to the cool air. The radishes freeze during in the night when the temperature drops down and defrost again in the sunshine during the day. This process is continued until the radishes dry up and turn a rich caramel color. The radishes become very sweet when dried. This is a typical, traditional food in the snow region.

Wow, now doesn’t that look delicious? I really want to try some of these dried diakons. What a beautiful way to preserve your food.