There used to be a dragline not far from me. It looked like a barn with a crane attached. First time I saw it, I was delivering a load of pipe. I parked about 250 feet away from this barn, and wondered what kind of crane was on the other side of the building. A loud buzzer sounded, and the boom picked up, and the barn started to swing around. Took me a moment to process what I was looking at. I got a quick tour. The barn, or cab swings slow enough that you can climb aboard while she swings, but as the operator pointed out, the end of the boom is moving a lot faster, and that bucket looked big enough to park a couple tandem trucks side by side.