Fukuden Spring flows from beneath a 50-m-tall cliff. This cliff was formed by lava that flowed from Mt. Chokai around 140 thousand years ago. Here you can see a pattern of cracks in the rock resembling a stack of thin boards. Known as platy joints, these cracks formed as the lava slowly flowed.

The volcanic rocks of Mt. Chokai hold a lot of water. Over time from several years to several decades, this water flows through the rocks and eventually out in natural springs like this one. The water at Fukuden Spring maintains a year-round temperature of about 12 ℃ and an average volume of 5 liters per second. This spring water is said to have encouraged and quenched the thirst of travelers coming and going along the road.