The Old McLean County Courthouse is an American Renaissance style structure built between 1901-1903. It is situated on a public square in the heart of the historical Bloomington Central Business District. Both the district and the courthouse are listed in the National Register of Historic Places.
The limestone-clad building of solid masonry construction is rectangular and symmetrical in plan and is executed in the Corinthian order. Rising from the roof are a limestone drum and copper dome said to be modeled after Rome's St. Peter's Basilica. The principal elevations are east and west, featuring three story porticos and a Corinthian pediment. A balustrade caps the cornice. The north and south faces are similar in appearance, featuring attached columns that rise to meet a pediment. The windows are decorated with Doric surrounds. In 2004 the dome and drum were restored. This project was funded by the County of McLean and a Public Museum Capital Grant from the Illinois State Museum-Illinois Department of Natural Resources.
The interior of the Old Courthouse structure is composed of quadrants set apart by broad hallways that meet in the center of the building to form a large and open three-story rotunda. This feature dominates the attention of the visitor. The rotunda rises over 100 feet in the center of the building and is finished at the top with an allegorical painting reprsenting peace and prosperity. The upper stories of the building are reached via a broad white marble stairway. This starway features bronze fish-scale screens embellished with laurel wreaths. The same screen closes the rails around the rotunda opening.
The halls are richly embellished with mosaic floors and an elegant wall treatment composed of white marble dado capped with antique verde serpentine stone. The moasaic tiles were laid by hand by Peoria Stone & Marble Co. The wine motif of the floor is associated with the Greek god Dionysus and the Roman god Bacchus, the gods of wine. Throughout the building there are a variety of floor finishes, including mosaic, marble, and maple.
Three original courtrooms are finished with decorative paintings, marble dadoes and scagliola. Only one original painting remains (pictured above) in what now functions as the Library reading room. Two courtrooms feature coffered ceilings. The ceilings in the hallways are decorated with plaster cornices and molded leaf and rosette decorations. Other architectural features include numerous beveled and leaded glass panels, scagliola door surrounds, solid bronze wall partitions, numerous original bronze combination gas and electric light fixtures, and marble counters. Honduras mahogany doors incorporate a rail and panel design, while beveled glass is used for decorative side lights and panels.