Royal errands day!

Kate Middleton -- er, Princess Catherine -- made one of her first casual post-wedding, post-honeymoon appearances in London on Thursday.

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Although Prince William's wife, 29, has been photographed at a couple formal events -- a meet-and-greet with President Barack and Michelle Obama, plus last week's Derby Day in Epsom, England -- Kate finally stepped out in everyday gear visiting hat-makers Lock & Co. Wearing a hot pink fuschia dress and a black cardigan, Kate wore her typical wedges, which showed off her impressively toned legs.

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The brand-new Duchess was surrounded by royal protection officers during the errand. But despite her now-royal status, England's future Queen still carried her own bags back to her car.

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Kate and William, 28, will be more dressed up later on Thursday evening, where they'll attend the 10th Absolute Return for Kids (ARK) Dinner. Held at Perk's Field (near their future home Kensington Palace), the glam gala will benefit the Foundation for Princes William and Harry.

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