The Knox County Courthouse is a historic building located on High Street in Mount Vernon, Ohio. It was built in 1855 in the Greek Revival style of architecture and was listed on the National Register of Historic Places in 1973. The Annex will be used for common pleas and juvenile/probate court hearings and proceedings. We modernized the space and beatified the facility with a new roof, windows, doors and ornate finish carpentry throughout the courtrooms.