Sunday was the final day of Rio 2016, which means all the athletes can celebrate at the closing ceremony.
Gymnast Simone Biles, who's taking home five medals, was picked to be the U.S. flag bearer for the Olympic ceremony.
Biles told USA Today she was a little nervous about carrying the flag because it's 9 feet long.
"I'm afraid the flag is going to be too heavy for me," Biles told USA Today on Sunday. "Michael Phelps is so much taller and he seemed to carry it so easily, and I'm very short. So I'm a little worried about that part."
Biles did just fine and even ended up having a selfie receiving line.
The Olympic flag was passed along to Yuriko Koike, the governor of Tokyo.
The Japanese national anthem played and video played, welcoming the athletes to Tokyo in 2020.
Shinzo Abe, Japan's prime minister, even made a special appearance. He dressed up a Mario and "transported" from Tokyo to Rio through a warp pipe.