Neilson Barnard/Getty Images for Mercedes-Benz

Attendees at Lincoln Center for New York Fashion Week were given a surprise treat when Carmen Dell'Orefice, the legendary 81-year-old fashion model, took to the runway twice in one day.

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Dell'Orefice, who often is referred to as the world's oldest working model, took to the runway around 9 a.m. Sunday in caramel gown by New York designer Norisol Ferrari. Just a few hours later she hit the catwalk again to strut her stuff, this time in a graphic print design by Finnish label Marimekko.

Dell'Orefice was born in 1931. The silver-haired American stunner launched her modeling career in the mid-1940s, and since gracing the cover of Vogue at the age of 15 has walked catwalks across the globe.

During both events, Dell'Orefice, who the past few years has modeled for Belgian luxury bag company Delvaux, Shades of Grey and Rolex, was joined by the 51-year-old American actress and model Carol Alt.

Dell'Orefice, who has been a fixture in the New York fashion world for decades, was later photographed with Olympian Ryan Lochte. The 28-year-old Olympic swimmer said in interviews this summer that he plans to launch a fashion line.