"A log barn in a field with an advertisement in faded ten-foot letters across the roofslope. See Rock City."
'See Rock City' barn on U.S. Highway 441, in Sevier County, Tennessee
GNU Free Documentation License'See Rock City' barn on U.S. Highway 441, in Sevier County, Tennessee - Credit: Scott Basford, April 2006

Though not the only advertisement or billboard mentioned in the book, this one is a solid clue to the book's setting, placing it firmly in the southeast US. Rock City is a tourist attraction, a natural rock formation on Lookout Mountain, near Chattanooga, Tennessee.

 

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