Marilyn Bell was a Canadian long distance swimmer who in 1954 became the first person to swim across Lake Ontario. At just 16 years old, she completed the swim in over 21 hours, defeating two other swimmers. Though she was not initially offered the $10,000 prize for completing the swim, she ended up receiving over $50,000 in gifts from supporters after her historic achievement drew huge crowds and interest in long distance swimming. Bell went on to have other successes, becoming the youngest person to swim the English Channel and the first woman to swim the difficult Straits of Juan de Fuca.

1. Charles Kim