The Mountains of Magic Kingdom - 24 Facts & Secrets

22 - You can trigger explosives on the mountain.

Yep, you can actually trigger “explosives” to go off on the mountain.  When you are in queue, pay attention to when you are in the Explosives Magazine room.  There will be instructions for how to use the cranks and plungers to set off the explosions.  Follow all directions and watch to see what happens.