In the farming community of Ronks, Pennsylvania, sits an immense collection on a miniature topic: toy trains. Roughly 500,000 materials spanning the 1800s to the present—books, periodicals, trade catalogs and price lists, instruction sheets and wiring diagrams, advertisements and fliers, photographs, files on American and world manufacturers and retailers, and convention souvenirs—make up the National Toy Train Library (NTTL), the noncirculating research library of the Train Collectors Association (TCA) and its National Toy Train Museum.