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.