According to BBC News:
Prince Charles laid a wreath on behalf of the Queen at the Cenotaph in London.
Ten thousand people – including veterans and relatives of WW1 soldiers – marched past the monument.
In France, where many of the battles of the Western Front were fought, 70 world leaders gathered for a ceremony at the Arc de Triomphe in Paris…
King George V announced that a two-minute silence would be observed in 1919… The silence continues to be observed every year on the 11th hour of the 11th day of the 11th month.
