Skis that size shouldn`t be left on a mountainside, they will be visible from space. :)
Leave them there. Eventually the Guardian or Enquirer or Globe will publish a story about the mysterious ski-like devices spotted from the ISS and speculate as to how many millennia they have been there.
Then Erich von Däniken will write another book citing them as proof of his thesis..
He IS past due for another one...