It was the dress that nearly broke the internet. Now its designer has revealed how it was made.
Designer Zac Posen has revealed on US television that it took six people 600 hours to make.
The gown was created using French Gossamer fabric.
To make the dress light up, LED lights and 30 mini battery packs were sewn into the lining.
"I’m interested in that place," Posen told Good Morning America, "where the past and the future meet, because that’s universal and that hits a chord around the world…just recognising beauty and a magic moment between fantasy and technology.’