In 2012, Katie Ledecky burst onto the scene as a 15-year-old swimming phenom at the 2012 Summer Olympic Games in London. Ledecky won gold by blowing away the field in the 800-meter freestyle.

She returned to Olympic glory in 2016, winning four gold medals and a silver in Rio.

Already an established swimming star, Ledecky went Stanford to swim for one of the nation's premier programs. During her freshman season, she set 12 NCAA records and nine American records while leading Stanford to its first team title since 1998. She followed that up a year by setting three more NCAA records, two more American records and helping the Cardinal win another crown. She decided to forgo her final two years at Stanford to turn pro because well ... she's Katie Ledecky.

Learn more about one of the world's best swimmers in this piece from NBC Sports Washington:

Ledecky took the mantle from Michael Phelps as the face of American swimming and has been a dominant force in the pool ever since. She swept gold medals in the 200-, 400- and 800-meter freestyle in 2016, setting world records in both the 400 and 800.

In the 2014 and 2015 Pan Pacific Championships, Ledecky won the 200-, 400-, 800- and 1500-meter freestyle races. Winning all four now is known as the "Ledecky Slam." The 1500 wasn't on the docket at the 2016 Rio games, but it will be this summer in Tokyo, where the American star can try and add an Olympic "Ledecky Slam" to her belt.