The Vienna Opera Ball has been at the heart of Austrian culture ever since the tradition began in 1814, and today it’s undoubtedly the highlight of the ball season.Dress code is strictly observed: floor-length white gowns for the debutantes and white tie and tails for their partners. Every year since the 1950s, the women have been crowned with glittering tiaras made using crystals from Swarovski. Traditionally created by a designer of renown, this year it was designed by a living legend: none other than Karl Lagerfeld. Crafted using 394 Swarovski clear and sapphire blue crystals and finished off with five Swarovski crystal pearls, it’s aptly called “Le beau Danube bleu.” The name not only echoes the curving ribbon of blue stones, it was also chosen to mark the 150th anniversary this year of Johan Strauss’ Blue Danube Waltz, the Opera Ball’s opening dance.On February 23, the tiara will be seen in all its glory. Gracefully adorning 144 debutantes at the Opera Ball, they will float in perfectly choreographed dance formation across the floor of the world’s most magnificent ballroom, the Vienna State Opera House.