The Johnson County Courthouse anchors the centre of Franklin's downtown square, a Richardsonian Romanesque building of 1883 with the kind of civic confidence common to county seats that peaked in the late 19th century. The rough-cut limestone exterior, arched windows, and central tower make it the most architecturally substantial building in town.
The courthouse still functions as an active county government seat, but the exterior and grounds are open to any visitor. The square around it is the commercial heart of Franklin and the gathering point for the annual Fall Festival.