Team Refugee had its first victory
Yusra Mardini, who had to swim for her life in 2015 when her boat capsized as she attempted to flee Damascus in the midst of the Syrian Civil War, won her 100m butterfly heat on Saturday.
Mardini is one of ten members of the first-ever Olympic refugee team.
The United States took home the first gold medal
The first gold medal of the games went to 19-year-old American Virginia Thrasher from Virginia, who received a near-perfect score during the 10-meter air rifle finals.
Great Britain's Adam Peaty broke a world record for the men's 100m breaststroke
Peaty completed his preliminary heat for the men's 100m breastroke in 57.55 seconds, nearly one second under the world record time, according to the UK Sun.
Greg van Avermaet won the men's road cycling competition
The Belgian cyclist came in first place after Great Britain's Geraint Thomas suffered a bad crash into a drainage ditch.