About This Video
To the east of Aki City, just a short stroll from Route 55’s road, lies the unassuming entrance to Ioki-do, a 40-meter-long, 3-meter-wide, and 5-meter-high tunnel adorned with fossilized shells embedded in its rocky walls. This remarkable cave was sculpted by the relentless erosion of ocean waves during an era when the region was surrounded by the sea that took shape more than 3 million years ago.
The canyon walls extending beyond the cave are adorned with a lush tapestry of predominantly tropical ferns. What sets this place apart is the exceptional diversity of fern species, numbering over 40 in total. In recognition of its uniqueness, it was designated a National Natural Monument as early as 1915.
Walking through this enchanting cave and continuing to explore the canyon can be a journey lasting anywhere from 20 to 50 minutes. Inside the cave, a gentle river flows, leading to the discovery of three hidden waterfalls tucked amidst the delicate emerald beauty of the Green World.
