[citation needed] Ontake is a major sacred mountain, and following shugendō practices, actors and artists have gone to the mountain to put themselves into trances to get divine inspiration for their creative activities.

[5] On Saturday, September 27, 2014, at around 11:53 a.m. Japan Standard Time (UTC +9),[6] the volcano erupted with a VEI of 3.

[7][8] The eruption was phreatic—caused by groundwater flashing to steam in a hydrothermal explosion—and there were no significant earthquakes that might have warned authorities in the lead up to it.

[9] The eruption was an extremely rare phenomenon, which made it difficult to take precautionary measures.

[13] The Japan Self-Defense Forces began helicopter searches for missing people after the eruption.