The glamorous 53-year-old cut an elegant figure in a taupe green Grecian-style dress. But what really made the outfit was her carefully selected choice of accessories.
Around her neck the mum of four wore a crystal necklace – made up of what appeared to be jade and pearls . And she complemented this with gold around her wrists – in the form of masses of hooped bracelets and a delicate watch.
A straw-look summer bag and vertiginous Christian Louboutin shoes finished off the chic ensemble.
Caroline was accompanying her brother Prince Albert to the exhibition of flowers, which is in its 43rd year.
Unlike last year, there was no sign of her husband, Ernst of Hanover, however. Caroline and her husband have not been pictured together for some time.
There has been wide speculation in the press that they are on the road to divorce, after Ernst was pictured kissing another woman on the beach in Thailand.
But Caroline did turn up to support her husband at his assault trial in January.