Special celebrations are taking place in Britain and the Commonwealth to mark the 90th birthday of Queen Elizabeth II.
Royal gun salutes were fired in London, while the Westminster Abbey bells tolled in the queen’s honor.
British Prime Minister David Cameron and opposition leader Jeremy Corbyn led tributes in the House of Commons to country’s longest-serving monarch.
“Her Majesty has been steadfast, a rock of strength for our nation, for our Commonwealth and on many occasions for the whole world,” Cameron said, adding that with her “unshakable sense of duty” the queen had provided counsel to 12 British prime ministers and met a quarter of all the U.S. presidents in history.
"Her Majesty has lived through some extraordinary times in our world, the prime minister said " ...As her grandson Prince William has said, time and again, quietly and modestly the queen has shown us all that we can confidently embrace the future without compromising the things that are important."
Labor Party leader Corbyn said Queen Elizabeth had served her country "with a clear sense of public service and public duty".
“Today we are talking about a highly respected individual who is 90. And Mr. Speaker whatever different views people across this country have about the institution, " Corbyn said, adding " the vast majority share an opinion that Her Majesty has served this country and has overwhelming support with a clear sense of public service and public duty, which the prime minister has just indicated."
Outside Windsor Castle, a royal family residence near London, people lined the streets as the monarch walked out accompanied by her husband, Prince Philip, to greet the crowd.
Queen Elizabeth cut a cake that won a British television contest, while the well-wishers were singing "Happy Birthday" and applauding. The queen and Prince Philip then traveled the streets of Windsor in an open top Range Rover.
The monarch unveiled a plaque marking The Queen's Walkway, a 6.3 kilometer trail that links 63 significant points in Windsor.
The British postal service has issued a series of 10 stamps to mark the milestone birthday.
Buckingham Palace released three photographs of the royal family taken for the occasion by renowned American portrait photographer Annie Leibovitz.