London (CNN) Britain will take extra security precautions to protect Queen Elizabeth II ahead of her speech Wednesday -- a member of Parliament will be held hostage at Buckingham Palace and guards with lanterns will check the cellars at the Palace of Westminster for explosives. These are just some of the traditions that go back hundreds of years but still ornament the annual event, in which the monarch lays out the incoming government's policy agenda and officially opens the new session of Parliament. Here's how the day will unfold:A hostage will be takenMembers of the Household Cavalry leave Buckingham Palace, where an MP was "held hostage" for the Queen's speech on May 25, 2010. Before the Queen leaves for the Houses of Parliament, a member of parliament is taken hostage and is locked away in Buckingham Palace. This tradition developed during a time when there was little trust between Parliament and the royals -- the lawmaker was held to ensure the monarch's safe return.

Source: CNN June 21, 2017 04:38 UTC