Sited on the center of a grassy square at the east end of the commercial district is the Richardsonian Romanesque courthouse. The square, dark red brick courthouse rests on a raised reddish-brown Jacobsville sandstone foundation and displays belt courses, windowsills, and lintels of the same sandstone. It has a complex hipped and gabled roof crowned by a central, pyramidal-roofed clock tower. The main entrance is recessed within a round Richardsonian arch. Intersecting broad corridors divide the main floor into quarters, each occupied by one of the four principal county offices—clerk, register of deeds, probate, and treasurer. The courtroom is on the third floor. Original decorative plaster wainscoting, wood chimney pieces, ceramic tile floors, pressed-metal ceilings, and staircases are found within. In 1892 voters of Mason County elected to bond the county to purchase property and build this courthouse. After advertising for plans, the building committee selected those prepared by Osgood (1845–1935), one of the leading architects in Grand Rapids and western Michigan, who designed four Lower Peninsula courthouses between 1887 and 1900. Charles T. Gatke built the courthouse. It was furnished by Grand Rapids School Furniture Company.