Adam reports on the Hillsborough tragedy
People across the country have stopped what they're doing to remember the 96 Liverpool football fans who died in the Hillsborough disaster 20 years ago.
They lost their lives on 15 April 1989, in Britain's worst sporting disaster.
The fans were at a football ground in Sheffield called Hillsborough to watch an FA Cup semi-final between Liverpool and Nottingham Forest.
Too many fans were allowed into the Liverpool end causing a terrible crush and 96 fans were killed.
People tried climbing over fences on to the pitch to escape - some were pulled to safety.
Ever since there's been controversy about whether more could have been done to save them.
Two-minute silences have taken place in Liverpool, Nottingham and Sheffield at 3.06pm, the exact time the game was abandoned 20 years ago to remember those who lost their lives.
A memorial service was also held, at Liverpool's football ground Anfield.
Fans have been leaving flowers at Anfield
After the Hillsborough tragedy, the design of British football grounds was changed so that the same thing would never happen again.
Premier League grounds now have to have seats for every fan and there aren't fences between the crowds and the pitch any more.