Some celebrities, philanthropists and Manhattan elite have no doubt already begun preparations for Monday's benefit for the Metropolitan Museum of Art's Costume Institute Gala, aka “the Met Gala.” As last-minute fittings and hair appointments are made throughout New York City, here's a look back at some of the big event's most memorable fashion highlights through the years.

The event has taken place every year since 1946, and it has been chaired by Vogue Editor-In-Chief Anna Wintour since 1995. This year, Wintour has made singer Taylor Swift an honorary chair, and she will preside over the event with help from actor Idris Elba and Chief Design Officer of Apple Jonathan Ive, among others. While celebrities like Swift attend for free, the rest of the attendees spend at least $25,000 each for a spot.

Lopez met gala Actress/singer Jennifer Lopez wore a daring red gown at the 2015 event. Photo: Getty Images

princess diana Diana Princess of Wales (left) and her close friend Liz Tilberis arrive at the Metropolitan Museum of Art in New York for the Costume Institute Ball in 1996. Photo: AFP/Getty Images

met ball Aerosmith lead singer Steven Tyler arrives with his wife, Teresa Barrick (left), and their daughter for the "Goddess: Costume Institute Benefit Gala" at the Metropolitan Museum of Art April 28, 2003 in New York City. Photo: Getty Images

Each year has a theme, as the gala serves as the opening for the Costume Institute’s new exhibition. The theme of this year's event is "Manus X Machina: Fashion in an Age of Technology.” The exhibit is set to explore the intersection between the intimacy of personal fashion choices and their creation in an increasingly technological world.

“Traditionally, the distinction between the haute couture and prêt-à-porter was based on the handmade and the machine-made,” Andrew Bolton, curator of the Costume Institute, told Vogue, adding, “But recently this distinction has become increasingly blurred as both disciplines have embraced the practices and techniques of the other.”

posh spice Former Spice Girl Victoria Beckham with designers Stefano Gabbana (left) and Domenico Dolce during the Met Gala in 2003. Photo: Getty Images

Jay-z and bey Jay Z and wife Beyoncé arrive at the 2015 event. Photo: Getty Images

kardashian west Kim Kardashian (pictured with rapper husband Kanye West) wore a daring dress in 2015. Photo: Getty Images

Wintour has long been both the event's organizer and one of its most interestingly dressed guests. The enigmatic editor usually makes a daring fashion choice while donning her usual oversized sunglasses. As the New York Times wrote ahead of last year’s gala, “It’s called the Met Gala, but it’s definitely Anna Wintour’s party.

wintour Vogue magazine editor Anna Wintour arrives for the 2003 event in New York City. Photo: Getty Images