The main library building was designed by the Chicago architectural firm of Patton & Miller and funded by Andrew Carnegie. The Beaux-Arts style building was constructed by Daniel Haring from 1903-1904. It is a two-story structure built on top of a raised basement. The exterior walls are composed of cut and dressed limestone. An addition was built in the rear of the original building and houses the main two-level stack area. A modern canopy was added over the entry at grade level to the basement. It was listed on the National Register of Historic Places in 1983.