Age: 19 (March 17, 1997)
Ties to Maryland: Grew up in Bethesda, where she attended Stone Ridge School of the Sacred Heart.
Career highlights: Ledecky burst onto the scene at the 2012 London Games with a lopsided victory in the 800-meter freestyle. She beat second-place finisher Mireia Belmonte Garcia by 4.13 seconds. … The 19-year-old is the most dominant freestyle swimmer in the world right now, and perhaps ever. She holds the world record in the 400-meter, 800-meter and 1,500-meter and won world championships in those three events, the 200-meter and the 4x200-meter relay in Kazan, Russia, last summer. … After comfortable victories at the U.S. Olympic Trials in the 200-meter freestyle (by 1.30 seconds), 400-meter freestyle (by 0.67 seconds) and 800-meter freestyle (by 9.86 seconds), she’ll swim all three events at the Rio Olympics.
Did you know? Ledecky’s best event is actually the 1,500-meter freestyle, which isn’t part of the women’s program at the Olympics. She swam it in 15:25.48 at the world championships last year, shattering her own previous world record by more than two seconds and beating second-place finisher Lauren Boyle by 14.66 seconds. … If she wins her three individual events plus the 4x200-meter freestyle relay in Rio, she will become the third American woman to win four gold medals in a single Olympics, joining Amy Van Dyken (1996) and Missy Franklin (2012). If she wins those four and swims and wins the 4x100-meter freestyle relay, she’ll break that record.