Sessho-seki, the Killing Stone

Above the old hot-spring town of Nasu Yumoto, the forest gives way to a barren, hissing field of yellow sulfur called Sai-no-Kawara — and in the middle of it sits the Sessho-seki, the “Killing Stone.”

Why It’s Interesting

Legend says the rock holds the vengeful spirit of Tamamo-no-Mae, a beautiful courtier who was secretly a nine-tailed fox demon; when she was unmasked and slain, her body became this stone, said to kill anything that touched it. The eerie, gas-venting field does nothing to dispel the mood. Then, in March 2022, the famous stone was found split cleanly in two — weathering, almost certainly, but the internet briefly and gleefully feared the demon had broken free.

Best Time to Visit

Year-round. The bleak sulfur field is most atmospheric under low cloud; late October rings the valley in autumn colour.

Getting There

It’s a short walk up from Nasu Yumoto Onsen, reachable by bus from Kuroiso Station — and the perfect spooky prelude to a hot-spring soak.