The official opening of Parliament in the UK is a ceremony held to mark the formal start of the parliamentary year, it is steeped in ancient traditions with one of the strangest being that the Queen holds an MP hostage in Buckingham Palace to ensure her safe return. This still goes on today with the hostage for 2014 being Vice Chamberlain Desmond Swayne.
This tradition dates back to the 17th century and the English Civil War where the monarch, King Charles I, and Parliament were on less friendly terms. Due to the hostility between the parties, King Charles was very distrustful of parliament and was so concerned for his life when entering that he decided to take a hostage to ensure his survival. He was right to be concerned, as he was eventually executed by parliament in 1649. However, nowadays the procedure is purely ceremonial though the hostage of the crown does remain under armed guard.
Another interesting tradition that takes place when the Queen opens parliament is that the cellars of the Palace of Westminster are searched by her Yeomen of the Guard in order to prevent a modern-day gunpowder plot such as was orchestrated by Guy Fawkes in 1605 where English Catholics attempted to blow up the Houses of Parliament and kill the Protestant King James I and aristocracy. The cellars have been searched every year before the monarch opens parliament since this event.