11.   The slope was covered with man-made snow, with four rows of nets along the most difficult sections to improve safety.

12.   With Christmas a week away, U.S. ski resorts from Aspen to Vail to Winter Park have cranked snowmaking machines into overdrive to cover their slopes.

13.   Mount Pendelikon, whose slopes are covered with dense pine and plane trees, is known historically for having provided the marble for ancient monuments including the Parthenon.

14.   The northern slopes are covered in ash and will not open.