Rio Olympics: Katie Ledecky Shatters 800m World Record in Freestyle Swimming

Katie Ledecky obliterated the field and her own world record in winning the 800m freestyle at the Rio Olympics on Friday, uniting the 200m, 400m and 800m titles for the first time since 1968.

The 19-year-old American, who also won the 4x200m relay for four golds overall, touched in 8min 04.79sec, beating the previous record of 8:06.68 she set in Austin, Texas, on January 17 of this year.

Ledecky, who shot to prominence with her surprise victory in the 800m free in London four years ago, touched almost half a length in front of her closest rivals -- silver medallist Jazz Carlin of Britain (8:16.17) and bronze medallist Boglarka Kapas of Hungary (8:16.37).

"I just wanted to lay it all out there," Ledecky said. "It was my last swim here at the Olympics, the pinnacle of our sport, and I have to wait another four years to have that moment. I just wanted to enjoy it all and put my very best swim out there."

Ledecky joined compatriots Janet Evans and Brooke Bennett as the only swimmers to win this event at two Olympics and now owns the top 11 times ever in the event.

Her dominant performance in Rio also included silver in the 4x100m freestyle relay.

She is the first Olympian to take the 200m, 400m and 800m gold at one Games since another US teenager, Debbie Meyer, achieved the feat at Mexico City in 1968 -- the year the 800m was added to the programme.

"I'm so proud to be part of history," Ledecky said, revealing that Meyer, a big fan, had been texting her mother, Mary Gen, during the week.

"She sent like a good luck video to my mom who forwarded it to me and I saw it right before I left before the session tonight," Ledecky said.

"I've really looked up to Debbie and all the women freestyle swimmers on the US team in general," Ledecky said. "We have a great history and I think we're making a lot of new history this week.

"Hopefully we'll inspire people through the years down the road when somebody's breaking my records."