Mandatory Credit: Photo by REX/Shutterstock (5725599n) David Cameron National Service of Thanksgiving to mark Queen Elizabeth II's 90th Birthday, St Paul's Cathedral, London, UK - 10 Jun 2016 Britain started a weekend of events to celebrate the Queen's 90th birthday. The Queen and the Duke of Edinburgh along with other members of the royal family will attend a national service of thanksgiving at St Paul's Cathedral on June 10, which is also the Duke of Edinburgh's 95th birthday