At the northern edge of the district is Bozu Jigoku ( Monk 's Hell ) , an obscenely bubbling mud pond where a Buddhist temple once stood until it was submerged in an earthquake back in the 15th century .
Bozo Jigoku , or Monk 's Hell , has sat at the northern part of the district ever since a Buddhist temple in the area was destroyed by an earthquake in the 15th century .