If the weather is nice and you are looking for a family friendly day trip from Iwakuni, I have just the place for you. Mine is a city in Yamaguchi Prefecture with over 25,000 residents. It is best known for Akiyoshidai Quasi-National Park. The area was thought to be a coral reef over 300 million years ago and was heavily forested 500,000 years ago. Eventually, the Japanese people utilized the area for farming which impacted the growth of the trees and changed the landscape of the area. When visiting the city of Mine, you can easily visit Beppu Benten Pond, Akiyoshi-do Cave, and Akiyoshi-dai Plateau for a full days worth of exploring.
Beppu Benten Ike
Beppu Benten Pond is a 4 meter deep pond known for its turquoise blue water. It is thought that the color of the water is from the various minerals from the limestone caves nearby. The temperature of the water is a constant 14 degrees Celsius no matter the time of year. People visit the pond to see the beautifully clear water and to drink the mineral water. It is said that drinking one glass of the mineral water will extend your life by one year. It is located at Beppu Itsukushima Shrine. The water from the pond is used for irrigation, drinking, and the trout farm adjacent to the shrine and pond. While I appreciated the beauty of the clear, turquoise water of the pond, I also enjoyed the rusty red minerals dispersed throughout the water, the moss-covered stone bridge, and the peaceful atmosphere of the grounds around the shrine.
Akiyoshido Cave is the longest cave in Japan with 8.79 kilometers of passages. It is also one of the longest caves in Asia. Currently, only one kilometer of the cave is open to the public for sightseeing. There are three entrances to the cave, but only two are used currently. During our visit, the path and entrance to the observation deck was closed. The observation deck leads to the Akiyoshidai Plateau where you can look out over the rolling hills, hiking trails, and karst.
Many fossils from the Pleistocene age have been found in the Akiyoshido Caves. Such fossils include the Japanese rhino, two types of elephants, a tiger species, and other animals. The cave is full of beautiful limestone and if you look closely at the ceiling or the walls of the cave, you may see small creatures called Shikoku-yokoebi which are freshwater amphipods. If you look up you may see tube-nosed bats flying overhead. The temperature inside the cave stays around 17 degrees Celsius year round and you can enjoy the sound of the water running through the cave.
Akiyoshidai Plateau is known for its limestones from the Paleozoic age. The plateau runs overtop the caves. The caves and the sinkholes are part of the underground drainage system in the area which created the unique topography of Akiyoshidai known as karst. It is Japan’s largest karst plateau. As you look over the landscape you notice numerous limestone pinnacles that can be as tall as 2 meters. The Quasi-National Park is Japan’s natural monument.
We really enjoyed exploring the area and would like to go back to the plateau to enjoy hiking the various trails in the lush countryside. It’s a serene and peaceful place to explore with friends or family. There are also some areas to relax or enjoy a picnic while taking in the beauty of the plateau.