The Steps Across the Water — Adam Gopnik

Ten-year-old Rose lives in New York, the city of bright lights and excitement, and a seemingly endless variety of people, architecture, and food--where extraordinary things happen every day on every block. But Rose wasn't born in New York; she was adopted as an infant from a far-away country. Though Rose loves her home and her adopted family, sometimes she can't help but feel different, like she's meant to be somewhere else.

Then one day in Central Park, Rose sees something truly extraordinary: a crystal staircase rising out of the lake, and two small figures climbing the shimmering steps before vanishing like a mirage. Only it's wasn't a mirage. Rose is being watched--recruited--by representatives of U Nork, a hidden city far more spectacular than its sister city New York. In U Nork, Dirigibles and zeppelins skirt dazzling skyscrapers that would dwarf the Crysler building. Impeccably dressed U Norkers glide along the sidewalks in roller skates. Rose can hardly take it all in.

Then she learns the most astonishing thing about U Nork. Its citizens are in danger, and they need Rose's help, and hers alone...