Shimabara Peninsula was the first place in Japan to be certified as a UNESCO Global Geopark. The peninsula is still pulled north and south, causing the earth in the middle to split apart and become a fault, making it easier for heat sources to rise up. This is the Unzen volcano. In 1991, Mount Unzen erupted, causing a large pyroclastic flow to flow from the mountain into the sea. This was the first time that the term “pyroclastic flow” was recognized in Japan, bringing with it terrifying memories.

The faults allow three different hot springs (Obama Onsen, Unzen Onsen, Shimabara Onsen) to bubble up, and spring water also bubbles up. In Obama Onsen, steam erupting from the earth can be used to make steamed dishes, just like in Beppu Onsen. Unzen Onsen was a summer resort where Westerners came to enjoy vacations to escape the summer heat of Shanghai and Nanjing during the time China was under colonial rule. Shimabara is famous as the place where the people suffering under oppression fought against the Tokugawa shogunate by not hidding Christian faith; after this, their descendants hid their faith throughout the long Edo period (as hidden Christians) until the Meiji.
If there hadn’t been a heavy snow warning, I would have enjoyed the scenery of Jigokudani (Hell Valley) in Unzen Onsen and the frost (a phenomenon in which ice freezes over the trees all over the mountain), which can only be seen at this time of year, but the roads were closed due to the snow, so I just left my car in Obama Onsen and took the shuttle bus to and from Unzen Onsen. It seems that this kind of experience is rare, but the heavy snow and low temperatures this year are abnormal.
However, the Shimabara Peninsula is rich in history and is full of things to see. When Toyotomi Hideyoshi unified the country, he changed the territory of this region and established an exclave (Kojiro-Kuji) of the Nabeshima Domain (present-day Saga Prefecture) on the Shimabara Peninsula as a check against the Shimabara Domain and Satsuma Domain. Although the kanji characters do not suggest such a reading, the area still retains the atmosphere of the Edo period district, and the streets lined with samurai residences remain as they were then. Kojiro-Kuji is perfect for a short stroll. The early-blooming cherry trees planted in front of the Nabeshima residence, whose original building has been preserved, were just about to bloom.



The Shimabara Railway, which runs leisurely along the coastline of the Shimabara Peninsula, and the Ariake Sea that spreads out behind it create a feeling of openness. It seems that the station buildings closest to the sea are advertised as a selling point in themselves, with the opportunity to take photogenic photos, and in the case of the Shimabara Railway, the most popular is Ohmisaki Station, but Kobe Station also has a nice, old-fashioned feel to it. The scenery is often used in commercials for soft drinks. If you check the timetable in advance to see if there is an up or down train coming, you won’t miss the chance to take a photo. Trains come about once an hour. However, all the local train lines are struggling financially, and there is talk of closing the Shimabara Railway and replacing it with buses. I hope the trains will continue.

Saying goodbye to the Shimabara Peninsula and heading to Nagasaki Airport, one must pass through Isahaya. Speaking of Isahaya, a major political issue in the past was whether to open or close the floodgates of the Isahaya Bay reclamation project. The river flowing into Isahaya was originally short, so heavy rains in the mountains directly led to flooding, and so reclamation work was carried out with the aim of improving drainage. However, after the reclamation work, which involved destroying the tidal flats and building long dike with closed floodgates, seaweed cultivation in the Ariake Sea suffered devastating damage. Fishermen filed an administrative lawsuit against the government, claiming that the floodgates had prevented the flow of abundant nutrients from the mountains into the Ariake Sea. The government’s response changed several times with the change of administration, and judicial decisions were also in disarray. In the end, the gates were not opened, and the matter was recently settled, but interest in the floodgates had already been lost among the public nationwide. I have heard that the color of the seaweed in the Ariake Sea is getting worse, but this is a nationwide story. A highway was built on top of the dike, but driving on it gives me mixed feelings, despite the beautiful scenery.
Once I cross the dike I enter Isahaya city. If I had the time, I would pay a lot of money to eat the famous steamed eel, but here I head to Isahaya Shrine to receive some of the good fortune that comes with this season. The torii gate is covered with a giant Otafuku face, and it is said that by passing through the mouth of this lucky charm, one will jump in and be granted good fortune. It is easy to hit your head when passing through, and if you do, you will be given a bump on the head instead of good fortune.

Isahaya Shrine was built by imperial command of the emperor during the Nara period and served as the general guardian of Kyushu. It was called Shimen-Gu, a name that comes from the Kojiki, an ancient Japanese historical book. In the past, people believed that misfortunes came from some directions, so this shrine is said to ward off misfortunes from all directions and bring good fortune. It is the same benefit as Jonangu Shrine in Kyoto, which is famous for its plum garden.
Detour (Potatoes from Nagasaki?)
Besides Isahaya, there is also another entrance to the Shimabara Peninsula, Tachibana Bay in the south. As the Geopark says, the Chijiwa Fault, which was formed when the Shimabara Peninsula was pulled north and south, can be clearly seen from the Chijiwa Observatory facing Tachibana Bay. However, what is important to note here is that potato cultivation in Japan began in Nagasaki, and even today Nagasaki potatoes are famous for their delicious taste. Most Japanese people associate potatoes with Hokkaido as their place of origin, but the Japanese name for potatoes, “jaga,” was named after Jakarta, where they were imported, and was improved in Nagasaki. However, the real place of origin of potatoes is the Andes. At Chijiwa Observatory, you can buy “Jagachin,” which are whole potatoes marinated in seven different seasonings and then deep-fried. Be sure to buy some and take a commemorative photo of yourself biting into it.
