Prince William and Kate Middleton's First Anniversary of Their Engagement (PHOTOS)

Prince William and Kate Middleton celebrate the first anniversary of their engagement on Thursday.

The couple were already secretly engaged, with William proposing to Kate during their Kenya trip. But it was on this day, a year ago, the couple decided to tell the entire world that after years of being together, and even a brief break-up in between, they were finally getting married.

William had proposed to Kate with the engagement ring that had belonged to the late Princess Diana. Kate confessed that she was excited and shocked at the proposal.

It was from then that Kate, from just being the Prince's long-term girlfriend, became one of the most followed women in the world.

Kate had then said: "Hopefully, I will take it in my stride", adding that William was "a great teacher." She seems to be doing a fine job as people world over are bowled over by the "Middleton charm."

Prince William said then that the ring "was very special to me" as was his bride-to-be. Giving it to her was "my way of making sure my mother didn't miss out on today."

The official announcement of the engagement was given by Clarence House on Nov. 17, 2010. They got married on April 29, 2011, at Westminster Abbey in a gala event watched by around a billion people all over the world.

The royal marriage of Prince William and Kate has been one of the great events in 2011 and for Queen as well.

The Duke and Duchess of Cambridge hosted a black-tie reception and dinner, at St. James' Palace in London, for the National Memorial Arboretum appeal.

Britain's Prince William and his wife Catherine, Duchess of Cambridge arrive at ARK gala dinner at Kensington Palace in London

Britain's Catherine, Duchess of Cambridge laughs as her husband Prince William speaks outside the official residence of the Governor General of Canada, Rideau Hall in Ottawa

Britain's Prince William and his wife, Catherine, Duchess of Cambridge applaud after Andy Murray of Britain defeated Richard Gasquet of France, on Centre Court at the Wimbledon tennis championships in London

Britain's Prince William and his wife Catherine, Duchess of Cambridge visit Victoria Barracks to present medals to the Irish Guards in Windsor

Britain's Prince William and his wife Catherine, Duchess of Cambridge, take part in Canada Day celebrations on Parliament Hill in Ottawa

Prince William and Catherine, Duchess of Cambridge, walk as they visit the Sainte-Justine Hospital in Montreal

Catherine, Duchess of Cambridge and Prince William, Duke of Cambridge, attend a reception at Calgary Zoo

Prince William and Catherine, Duchess of Cambridge arrive at the Summerfield Community Centre in the Winson Green area of Birmingham, central England Aug. 19, 2011