The cutter head carves a smooth round hole through the rock -- the exact shape of a tunnel. Conveyor belts carry the rock shavings through the TBM and out the back of the machine to a dumpster.

Cutting through a mountain is hard work! Choose a tool or technique below, and try to figure out the best way to chew a mile-long railway tunnel through this mountain! Hint: The tunnel score will ...

A fiery pileup inside a tunnel on Interstate 80 in Wyoming left at least two dead with five others injured late Friday morning. Fire and smoke billowed from the tunnel as people ran for safety.