sentences:  On 4 June 2011, in their first public outing since returning from their Seychelles honeymoon, Prince William, Duke of Cambridge, and his wife, Catherine, Duchess of Cambridge (along with the Queen, William's brother, Prince Harry, and Catherine's parents, Michael and Carole Middleton) attended the 2011 Epsom Derby at the track.The racecourse is between Epsom, Tadworth and Langley Vale.As it is in a public area, people can watch the Derby free, and this meant that the Derby used to be the most attended sporting event of the year.