article_snippet.sent: The trail, which runs down the mountainous spine of the island, happens to be the toughest trek in Europe.
article_snippet.sent: The Corsican Mouflon, or mountain sheep, make easy work of the tough GR20 hiking trail .
article_snippet.sent: the tough GR20 hiking trail runs down the mountainous spine of Corsica and happens to be the toughest trek in Europe Europe .
highlights_snippet.sent: Sign-posted route is an easier equivalent to the famed GR20 hiking trail .
  