This was called to my attention by reader Douglas Swartzenruber, who put it on his website, “A View from Planet Boulder”. (Do not click the link yet).
First, there are these “moguls” made by skiers; Douglas explains:
For any non-skiers out there, moguls are formed on steeper slopes when numerous skiers follow the same route down and push snow to the side on each turn. The snow begins to stack up and as more skiers follow the same line, the moguls grow, sometimes reaching heights of over 6 feet. I have never been a fan of skiing moguls [not enough talent], but if you want to be impressed with mogul skiing, watch these incredible folks ski the bumps.
But then there are these moguls—on a fence. Who made them? Now you can click the link to see the answer: