Kate Middleton Schleps Box, Uses Visitors Entrance at Palace

Kate Middleton
 Houghton/Splash News Online

Kate's keepin' it real!

Although she's marrying royalty — nay, the heir to the British throne! — in less than 48 hours, Kate Middleton didn't put on any airs visiting Clarence House on Wednesday.

At the palace — her future home — for a wedding rehearsal, common-born Middleton, 29, looked chic but casual in jeans, a white top and wedge heels.

According to multiple witnesses, Prince William's fiancee actually entered Clarence House through the visitors' entrance (she's still a visitor at the royal residence until Friday!).

Adding to Middleton's unassuming demeanor, she exited Clarence House around 4 p.m. schlepping a sizable brown cardboard box — contents unknown — into the trunk of her blue Audi A3.

After re-entering Clarence House, Middleton emerged outside about an hour later, chatting on her cell phone. warmly greeting a pal, and carrying her own dress bag plus a small posy of flowers.

"Everyone's happy," a Clarence House worker told Us Weekly late Wednesday. "The atmosphere is really great!"

For more on the Royal Wedding, including rare photos, interviews with family and friends, details on Kate's new life as a princess and a tour of their lavish homes, order a copy of Us Weekly's Will & Kate: The Royal Wedding now.

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