In 1888, Jefferson County voters passed a $40,000 bond issue to build a permanent courthouse as flourishing gold and silver mines and the arrival of the railroad drove rapid population growth between 1870 and 1890. Seeking a building that reflected confidence in the future, county commissioners hired Montana Territory architect John Paulsen, who designed a Richardsonian Romanesque courthouse inspired by the enduring structures of the Middle Ages and suited to a frontier community intent on showing its permanence. Contractor J. S. McKenzie built the two-story building from locally quarried granite and bricks burned within a mile of the site. Its massive form includes a tall square tower capped by an octagonal spire, two turrets, semi-circular arches, rough-cut stone accents, an asymmetrical roofline, and gargoyles below the eaveline. Inside are elaborate woodwork, decorative door and window trim, an ornately carved staircase, and a courtroom with walls rising twenty feet to a ceiling of stained beams and planking. Completed the year Montana achieved statehood, the courthouse ultimately cost approximately $50,000 and remains one of the oldest courthouses in Montana still used for its original purpose.