10. The Monongah Mining Disaster
The Monongah mining disaster is the worst in US history. On December 6, 1907, the West Virginia mine was known for having an extensive maze of underground tunnels. Around 10 am, an explosion went off in one of the sections. However, that explosion triggered an even bigger explosion in another part of the mine.
This second explosion not only collapsed the entrance to the mine but destroyed the ventilation system, which caused the shafts to fill up with poisonous gases. Sadly, because of this, the men and boys (yes boys) who survived the two blasts tragically perished from suffocation or poisoning. The cause of the explosion was never established, but it took the lives of 361 miners that day.