We have seen different natural ice or snow formations in places that see very cold temperatures in winter. Northern parts of Japan usually witness much more natural ice wonders in the cold season. One of such is Omiwatari (御神渡り) which literally means “The Passage of Gods” or “The God’s Crossing.” Let’s see what it is all about!
Omiwatari is an ice ridge that is formed across the frozen Lake Suwa (諏訪湖) in Nagano Prefecture (長野県) during winter. Ice ridges are common in frozen lakes of northern temperate regions. The main reason for the formation of an ice ridge is the difference in day and night temperatures. If the days are warm/sunny and the nights are cold, it causes cracks in the ice. The cracks create a sound called “ice thunder” which is a loud booming sound like a thunder. Thin broken ice pieces come up and gather together forming a ridge.
Watching ice formation or breakup is an activity done by many nature lovers. A guy named Olof Ahlom began maintaining records of ice breakup in the Torne River that flows from the Arctic to the Baltic Sea since 1693. The tradition still continues to this day with many people contributing to the study. Many Shinto saints have been observing the Omiwatari since the 15th century. They have complete data of the climate and the ice formation from then onwards. Scientists have found rapid changes in climate over centuries with the help of those data sets and are warning us of global warming.
The legend behind the Omiwatari that is believed by many locals is very interesting. There used to be a goddess named Yasakatome-no-kami (八坂刀売神) and a god named Takeminakata-no-kami (建御名方神). It seems that the goddess moved to the lower shrine at the other end of Lake Suwa; the god being unable to cross the lake, waited until the lake got frozen and walked over the ice to meet her. His footsteps are considered to be Omiwatari and people revere it as a sign that they could safely walk on ice.
Due to the climate change, Omiwatari is now seen less. The last one was said to be observed on the 22nd of January, 2013. It is not sure when to expect it as the winters are not really cold enough anymore due to the greenhouse effect.
Do contact the Suwa Tourist Information to ask about the possibility of Omiwatari. If there is a chance, you should definitely pay a visit to see this wonderful natural phenomenon with your own eyes.