thin ice. On average, 10 people a year have died in such crashes in Minnesota alone, with alcohol a contributing factor in many cases. In Saskatchewan, 16 out of 21 deaths in snowmobile collisions between 1996 and 2000 were caused by the effects of alcohol. Wrestler Lindsey Durlacher died in 2011 following surgery for a broken sternum he sustained in a snowmobile accident. Fatal collisions with trains can also occur when a snowmobile operator engages in the illegal practice of "rail riding", riding between railroad track rails over snow-covered sleepers. Inability to hear the sound of an oncoming train over the engine noise of a snowmobile makes this activity extremely dangerous. Collision with large animals such as moose and deer, which may venture onto a snowmobile trail, is another major cause of snowmobile accidents. Most often such encounters occur at night or in low-visibility conditions when the animal could not be seen in time to prevent a collision. Also even when successful, a sudden maneuver to miss hitting the animal could still result in the operator losing control of the snowmobile. A large number of snowmobile deaths in Alaska are caused by drowning. Because of the cold weather in many parts of Alaska, the rivers and lakes are generally frozen over during certain times of the year in winter. People who ride early or late in the season run the risk of falling through weak ice, and heavy winter clothing can make it extremely difficult to escape the cold water. While a snowmobile is heavy, it also distributes its weight at a larger area than a standing person, so a driver who has stopped his vehicle out on the ice of a frozen lake can go through the ice just by stepping off the snowmobile. The next leading cause of injury and death is avalanches, which can result from the practice of highmarking, or driving a snowmobile as far up a hill as it can go. During the 2018–2019 season, 7 snowmobilers in the United States were killed. Avalanche safety education is critical for those accessing the backcountry. Risks can be reduced through education, proper training, appropriate gear, attention to published avalanche warnings and avoiding drinking alcohol. In some areas of Western U.S., organizations provide avalanche training, some of which is free. It is recommended that snowmobile riders wear a helmet and a snowmobile suit. Types of races The International