Welcome to Iwaya-Iwakage Megaliths

Photo of Iwaya-Iwakage by IR. All photos are restricted. 

This Iwakage blogsite gives you an introduction to the megaliths of Kanayama, and especially the Iwaya-Iwakage megaliths. All photos shown on this blogsite are the property of either professional photographer Shiho Tokuda (indicated by ST) or me (indicated by IR). Please do not use our photos without our permission. 

Hello, I am Iwaya Rockbat, your guide to Iwaya-Iwakage. I would like to invite you to visit our megaliths in Kanayama town of Gifu Prefecture, in Central Japan. We have a marvelous site of huge boulders shaped by human hands thousands of years ago. What are the megaliths for? To observe the movement of the sun and thereby determine a nearly perfect solar calendar.

Iwaya   いわや  岩屋 means cavern or grotto. The second kanji itself is iwaya, cavern. Together with iwa, boulder, it emphasizes a cave made of boulders. To us it means more: a human-made megalithic structure with an interior chamber like a house. Moreover, the word iwakage means shade of the megaliths when we are inside the cavern.  My deepest wish is to share with you, dear Reader, this living treasure which is a monument to the study of our solar calendar as measured by our megalithic ancestors. This is moreover a monument to the great capacity of the human mind and the endeavor to bequeath to us such a magnificent solar observatory. This observatory has been operating for thousands of years, and for at least three thousand years has been determining four-year and 128-year leap year cycles with super-high accuracy. The Kanayama solar calendar is finer than the Gregorian calendar that we use. You will learn all this here, and more. Please enjoy your visit to this blogsite, and please visit us at Iwaya-Iwakage.

The Megaliths of Kanayama

The magnificent megalithic sites of Kanayama are found among the trees next to a bubbling stream in the Iwaya Valley close to the Iwaya Dams. When the dams were built to harness the Mazegawa in the 1960s and 70s, many remains of the Jomon period were found. The Jomon period lasted from about 12,000 BCE (possibly 14,500 BCE) to 300 BCE. These megalithic constructions were built thousands of years ago, perhaps around the time of the Egyptian pyramids since there are certain similarities of solar calendrics.

There are three groupings of the Kanayama megaliths, two close to each other in the Iwaya Valley and one due east on top of the nearby Higashinoyama mountain. The three clusters of megaliths are referred to as Higashinoyama (eastern mountain), Senkoku-ishi (carved stone), and Iwaya-Iwakage (boulder chamber). Although the presence of the megaliths was known to the local residents, and indeed there are a torii and little shrines indicating a sacred site, the why of the megaliths was a mystery. In the late 1990s Y. Kobayashi and S. Tokuda began investigating them. The information which I present to you is made available through the gracious courtesy of Kobayashi-san  and Tokuda-san. Their website is here:  http://www.seiryu.ne.jp/~kankou-kanayama/megaliths/index.html, and their Japanese blog here:  http://blog.livedoor.jp/kanayama_tour-kanayamamegaliths/archives/cat_568477.html.

It is remarkable that a solar observatory can be efficient even in the mountains at north latitude 35 degrees all year round. This is possible due to ingenuous design and astute selection of location.