There was a great article last weekend in the Wall Street Journal about the Betsy-Tacy books, described by Meg Cabot as "a delicious series of novels set in turn-of-the-century Mankato, Minnesota."
These were my favorite books as a kid (I desperately wanted to be Betsy, the main character) and I have read them many times since. The series starts at a fifth-grade reading level and gets a little more advanced as Betsy grows older. We Betsy-Tacy fans are are a small but very passionate bunch.
The author, Maud Hart Lovelace, grew up in Mankato (known as Deep Valley in the book.) A few years ago I was sent to Minneapolis to interview Pat Benatar for Rolling Stone (one of my rules, outlined in my first book, is to interview rock stars outside of New York or Los Angeles if you can - you avoid hordes of press, and the rock star may actually be glad to see you.) I brought along my sister Dinah to keep me company. After I interviewed the delightful, flinty Pat, I persuaded Dinah to drive me to Mankato, where Maud's house (the basis for Betsy's house) still stood, as well as the house of Maud's best friend Frances, on whom Tacy is based.
Dinah understood my obsession and kindly took the wheel while I explored the Betsy-Tacy hot spots of Mankato, including the Big Hill that Betsy and Tacy used to Climb. I was of course winking back tears the entire time.