"We are marking our one-year anniversary here," Obama told one surprised guest. To another startled visitor, she simply said, "Surprise!"
Like most political figures, Obama is practiced in the art of chit-chat. For about 45 minutes, she asked a steady stream of tourists where they were from and how they were enjoying Washington.
Photo: By Samantha Appleton, The White HouseCourtesy: USA Today: OVAL Blog
Video: The Washington Post