I didn't know some of this, thanks! I used to live near an active train yard, and one of the warnings people gave me when I moved there was the sound caused by

I didn't know some of this, thanks! I used to live near an active train yard, and one of the warnings people gave me when I moved there was the sound caused by the trains "stacking" (which is the noise caused by each of the car couplings pulling out of their slack). I thought it was a drawback at first, but now that I've moved away I kind of miss it.