The worst, I personally Witnessed
This thread will not be for the squeamish.
I was in my twenties. Climbing Monteagle, TN., before the Interstates.
There sometimes would be twenty trucks or more climbing at the same time in a line.
In 4th., on a straight, still climbing, the opposite switchback was visible.
Truck comes head on, over the edge, Driver jumps, but too late. Bounces off the side of the trailer, arcs over, to in front of the rig, it twists to the Driver's side. Bounces off the ground, the Driver underneath.
Slides down the mountainside, out of view, fuel tanks explode.
All of us kept climbing, there was nowhere to pull off.