The old Iroquois County Courthouse was constructed in 1866, with two additions built in 1881 and 1927. In the early 1960's an Iroquois County resident, Mrs. Katherine Clifton, bequeathed to the county in her will a large sum of money and a site upon which to build a new courthouse. The old courthouse was advertised for sale and fell into disuse. In 1967 during the Centennial Celebration of Watseka, the Iroquois County Historical Society was organized, and circulated petitions throughout the county not to sell the Old Courthouse. The petitions were approved by the County Board of Supervisors, and the Old Courthouse re-opened as a museum that same year.

Today, a visit to the Old Courthouse is a step back in time where you can visit the old County Jail, see re-creations of an old-time back porch, a Victorian parlor, old time general store, post office, one-room schoolhouse and much more.

It is a place where you can stroll past showcase after showcase featuring one-of-a-kind treasures of a bygone era, with something to interest nearly everyone: fossil and mineral collections, Indian artifacts, the latest fashions of the Victoria era, a collection of over a hundred antique dolls, medical instruments from the pioneer days...and much more.