Kate Middleton made an incognito visit to London’s National Portrait Gallery

A day before visiting the Royal Marsden, Kate Middleton made an incognito visit to London’s National Portrait Gallery. The Duchess of Cambridge spent the afternoon touring the contemporary collection downstairs with a small group of curators, says an onlooker.

Kate, who studied art history at St. Andrews University seemed interested in Marc Quinn’s Self, a self-portrait cast of the artist’s head made from his own blood and then frozen.

“She was asking lots of questions and talking to the experts at length about the piece,” says the eyewitness.

Because the gallery downstairs is split into many side rooms, Kate was able to move around without too many people noticing her. She also viewed a portrait of Princes William and Harry on her way out.

“She didn’t spend a huge amount of time looking at it,” the onlooker notes. “She just smiled and admired it briefly.”