 In 1869, due to its importance as a major transportation hub, the county seat was moved to Clinton; it has resided there ever since.The Clinton County Court House, located at 612 North 2nd Street, was designed by G. Stanley Mansfield, Architect, of Freeport, Illinois, and Josiah L. Rice, Supervising Architect, of Clinton.It was constructed between 1892 and 1897.