Platinum Jubilee celebrations are taking place across the UK in honour of Queen Elizabeth II. The Queen has sat on the throne for 70 years now, a feat that has never been seen before in British Monarchy history. Crowds have cheered Britain’s Queen Elizabeth in London as the UK celebrates her Platinum Jubilee. The 96-year-old has been on the throne for seven decades – the longest reign by a British monarch. Thursday is the first of four days of events to mark the milestone.