Kate, Duchess of Cambridge, enjoys her first solo public appearance

As one of the most photographed women in the world, the Duchess of Cambridge knows a thing or two about portraits.

So, it was suitable that her first solo public engagement was at the National Portrait Gallery Wednesday. (Her husband, meanwhile, is 7,500 miles away in the Falkland Islands for work.)

Kate, 30, stepped out on a bitterly cold London night in a grey tweed dress by Jesire and black four-inch heels.

Gallery: Evolution of Kate Middleton

She was at the gallery, one of her chosen charities, to view a special collection of Lucian Freud's work.

An art history major at St. Andrews University, Kate greeted photographer Mary McCartney and Freud's daughter, Bella, at the museum.

"She took an interest in all of us. She said she'd been on my website and seen my pictures – which made me blush," McCartney, a gallery trustee, said. "It's so exciting she's become involved. She's refreshing."

Next week, Kate is expected on a Valentine's Day visit to Liverpool to see the work of another one of her charities, Action on Addiction.