Great Britain is in mourning as Her Majesty, Queen Elizabeth II passed away during the early afternoon of Sept. 8.

Operation London Bridge, the plan for what to do once the Queen died, has begun. The operation’s name comes from the secret code, “London Bridge is down,” created for announcing the Queen's death to the prime minister.

After the prime minister knew, the Foreign Office had to announce the Queen’s death to the former colonies of the British Empire where she is still the head of state. After that, the news was posted on the Royal Family’s website and Twitter before it was sent to news stations all over the world.

The period of the UK’s 10 day national mourning has begun. The flag at Buckingham’s Palace and all flags across Britain are all to be lowered to half-staff until the period of mourning has ended.

The Queen’s coffin will stay in Buckingham’s Palace for a few days before being moved to Westminster Hall. There, public citizens will probably be able to pass through and pay their respects. Her Majesty’s funeral will take place at Westminster Abbey.

As per traditional protocol, at the funeral there will be a moment of silence before the Queen’s coffin will be placed on the ancestral Windsor carriage. That carriage will take her to Windsor Castle to be buried alongside her family and husband.

When the Queen died, her son Prince Charles became the new monarch. As king, he is also Britain’s new head of state for the former colonies of the British Empire. He also has a few major duties and proclamations to announce.

First, Charles must give a declaration at his political inauguration. Second, he must take an oath to the Church of Scotland and a vow to maintain the Protestant monarchy.

At 11 a.m. on Sept. 9, an announcement was made to officially declare Charles as his Royal Majesty, King Charles. The National Anthem will be changed back to “God save the King.” Those in Parliament have to take an oath to the new king. This will all be new for British citizens younger than 70, as they wouldn’t remember a time where there was a king.

It will be months before Charles’s formal coronation, and months before Great Britain has finished their informal time of mourning.

“God Save the King.”