(Translated by Google) When you enter Nanatsugama Park, the parking lot and toilet are on the right side. Campsite facilities are on the left. If you go further, you will see a structure called an observation parking lot.
There are parts of the slope that have collapsed due to Typhoon No. 19 in 2019, and the walking path has collapsed, so it is not possible to go from Nanatsugama Park to Bentendo.
When I visited, I passed the Nanatsugama Campsite and parked at a fairly large observation parking lot. From there, go down the stairs to the observation plaza, and you can see part of Nanatsugama below. If you look down from above, you won't be able to see the whole thing because it's in a halfway position.
However, the thin columnar joints that appear to be arranged in regular order spread out before your eyes and are worth seeing. Some website says that in order to see the waterfall up close, you need to walk down a steep slope, so I wonder if it's possible to go near the waterfall basin from the direction of Bentendo. I wasn't able to go to Bentendo this time, but if it's restored when I'm nearby, I'd definitely like to stop by.
The Kama River, which is dotted along the Kama River mountain stream that flows from the Naeba Mountains, is a series of seven waterfalls and waterfall basins spanning approximately 1 km, and has been designated as a nationally designated scenic spot and natural monument.
The geology in this area is Neogene andesite, and the andesite has well-developed columnar joints. The left bank of the Kama River has vertical layers, while the right bank has cross-sectional layers, making this a very unusual landscape even from an academic point of view. Because andesite is hard, and because of its columnar joints, it is vulnerable to mechanical damage, which led to the formation of waterfalls and the formation of a giant waterfall basin underneath. Columnar joints develop in various directions, from vertical to horizontal, and these changes seem to play a role in the formation of waterfalls and basins.
These waterfalls are Benten Falls, Ninotaki Falls, and Fudo Falls from upstream. It is called Nakano Falls, Maki Falls, Kannon Falls, and Mitarai Falls. The waterfall basins (pots) range in depth from approximately 1.5 meters to 6.3 meters, and Fudo Falls, which has the largest depth and area, is said to have been built in ancient times because a man broke his promise to Benten and cast a net. Apparently, the ``Legend of the Seven Pots'' is said to have been told that he lost his life after angering the serpent that was the owner of the waterfall basin.
The entire waterfall collapsed due to a landslide in 1995, but restoration work was carried out, and in the fall of 1997, Japan's first sabo dam made of pseudo-rocks was completed, and the current form is a restoration close to the waterfall before the collapse. It seems to be the condition.
In addition, the Nanatsugama Festival is held every year in mid-July, and the traditional performing art of Tashiro Kagura is performed.
Before coming here, I also stopped by Kiyotsu Gorge, but I felt that this was a much more spectacular view in terms of admiring the columnar joints. If you are planning to visit Kiyotsu Gorge, you should definitely visit this place. Perhaps because it was late, or because there were no regular visitors, there were no people around, so I was able to enjoy the view at my leisure.
(Original)
七ツ釜公園に入ると右側に駐車場とトイレ。左側にキャンプ場施設。さらに進むと展望駐車場という構造になっている。
令和元年の台風19号により法面が崩落している部分があり、散策路崩落の為、七ツ釜公園から弁天堂へは行くことができないとのことだ。
訪問時は七ツ釜キャンプ場を通り越して、かなり広めの展望駐車場に停車した。そこから階段を降りて、展望広場に行く途中で、眼下に七ツ釜の一部を見ることが出来る。上から見下ろすと位置が中途半端なので、全体を見渡すことはできない。
しかし眼前広がる規則正しく整列したかのような細い柱状節理は一見の価値がある。どこかのHPで滝を間近でみるためには、急傾斜を徒歩で下りる必要がありますと記載があったので、弁天堂の方面から滝壺近くに向かうことが出来るのだろうか。弁天堂へは今回行くことができなかったので、また近くに寄った時には復旧してくれていれば、是非寄ってみたい。
苗場山系から流れ出る釜川の渓流に点在する釜川は、七つの滝と滝つぼが約1㌔㍍にわたって連続して構成されており、国指定名勝・天然記念物に指定されている。
このあたりの地質は新第三紀の安山岩が分布し、安山岩には柱状節理がみごとに発達しています。釜川の左岸は縦層、右岸は断面層という学術的にも大変珍しい景観となっている。安山岩が堅いことと同時に、柱状節理のせいで機械的破壊に弱いため滝が形成され、その下には巨大な欧穴である滝壺ができた。柱状節理は垂直なものから水平方向のものまでさまざまな方向を向いて発達しており、このような変化が滝や滝つぼの形成に役割を果たしているそうだ。
これらの滝は上流から弁天滝、二の滝、不動滝。中の滝、巻の滝、観音滝、御手洗滝と呼ばれている。滝つぼ(釜)は深さ約1.5㍍から6.3㍍のものがあり、最大の深さと面積をもつ不動滝には、その昔、男が弁天様との約束を破り「投網」を打った為、滝壺の主である大蛇の怒りを買い、命を失ったという「七ツ釜の伝説」が伝えられているそうだ。
平成7年の土砂災害により滝全体が崩壊した為、復旧がなされ、平成9年の秋に全国初の擬岩による砂防ダムが完成し、崩壊前の滝に近い型で復元された形が今の状態だそうだ。
また毎年7月中旬に七ツ釜まつりが開催されていて、伝統芸能田代神楽の上演が行われるとのこと。
ここに来る前に清津峡の方にも寄ったが、柱状節理を鑑賞するという意味では、こちらの方がよっぽど凄まじい景色だと感じた。清津峡に寄る予定がある方は是非こちらにも足を運んだほうが良いだろう。時間も遅かったせいか、それとも普段から訪れる人が居ないのか、人は全く居なかったのでのんびり鑑賞することができた。