Mary Riddell began skiing at the age of three at Durango/Purgatory Adaptive Sports. She qualified for the US Adaptive Ski Team when she was 14 years old and for the next nine years she was a dominate figure in national and international competition. Riddell won six Paralympic medals including two Gold. She also won six World Championship medals, two of them Gold. In addition, she won three World Cup Overall Globes, 11 individual event World Cup Globes, and multiple National titles. During the 2000/2001 season, Riddell was on the podium at every World Cup race.