In "Dude, We're Getting the Band Back Together" Danny sings in "History of Rock" that "When I was a boy, down in South Illinois..." Which hints that Danville may perhaps be Danville, IL. It's within a day's drive of Mount Rushmore (although it's 17 hours according to Google ...
DANVILLE PUBLIC LIBRARY319 NORTH VERMILION STREETDANVILLEIL61832(217) 477-5220 DANVILLE PUBLIC LIBRARY511 PATTON STREETDANVILLEVA24541(434) 799-5195 DANVILLE-CENTER TOWNSHIP PUBLIC LIBRARY101 SOUTH INDIANA STREETDANVILLEIN46122(317) 745-2604 MT. HERMON BRANCH LIBRARY2725 FRANKLIN TURNPIKE, SUITE JDANVILL...