The historic Waterloo Library was built in 1883 in the Queen Anne style. Founded in 1875, it is one of the oldest libraries continuously operating in the state. It features a 140-seat venue called Fatzinger Hall that hosts lectures, musical and theatrical performances, readings, and other events. A modern addition, Terwilliger Museum, was built in 1960 and features exhibits about Waterloo's history. Numerous items and artifacts are on display including vehicles, Native American artifacts, maps, photographs, currency, antique guns, and dolls. The library was added to the National Register of Historic Places in 1996.
The library's history dates back to 1830 when the Waterloo Library Association, the predecessor to the Waterloo Historical Society, was established. The Society was formed in June of 1875 but later was incorporated by the state to become the Waterloo Literary & Historical Society. In March the next year, the organization changed its name to the Waterloo Library & Historical Society. The library itself took three years to build.