Making Gravel

My neighbor had warned me that when the gravel pit on his land started making gravel, it would be loud.  They've started.  I can hear the operation going when I'm outside but the sound isn't so much loud as it's a constant background noise.  Until I watched them put this site together I thought you just dug gravel, as is, out of the ground.  Maybe there are places you can do that but here, at the far right in the picture is a rock crusher that is fed large rocks and bounders.  It breaks them up and that is mixed w/ sand.  From there it goes up the conveyer so it can be dumped in the one large pile on the far left of the picture.   I learn something new every day.