Have you ever heard of Kenashi Pass (毛無峠) in Nagano?
This place is located between Gunma and Nagano Prefecture. Though there used to be a town before, now nobody lives here.
Since the clod is sulfur-rich, people (around 2000) who worked for mine habited.
In 1937, 245 people died in sediment disaster. In spite of disasters, people continued digging until 1971.
Now the land is still friable and it is dangerous to reach place where town was located.