According to German consulting firm Montenius Consult, which on Tuesday released its annual study into the world's largest ski areas, many resorts exaggerated the size of their slopes, especially in France and Switzerland.
Of the 56 biggest ski areas in France, 38 inflated their piste length by more than 30 percent, while three resorts said their slopes were more than double their actual size, the study found.
Of 62 Swiss resorts, 33 amplified their piste length over 30 percent and nine percent doubled the length.
German expert Christoph Schrahe, who spent hundreds of hours measuring pistes to compile the report, said France's Alpine Savoie region was home to the world's two biggest skiing domains.
The Trois Vallees area, making up eight stations including the chic Courchevel, Meribel and Val Thorens resorts, is the biggest with a combined 542 kilometres (336 miles) of ski slopes, while the Paradiski zone comes in at 402 kilometres.
Third on the list was the American ski area of Park City/Deer Valley in Utah, which has jumped from 33rd into third place thanks to a new gondola connection which gives it 360 kilometres of pistes.
The United States has 28 of the 100 biggest ski areas, while France has 20 and Austria 17.