The Mason County Courthouse is a courthouse located at 300 East Ludington Avenue in Ludington, Michigan. It was listed on the National Register of Historic Places in 1988. The first courthouse in Mason County was located in the two-story home of Burr Caswell, who turned over the home to the county in 1856. In 1861 the courthouse was moved to a …The Mason County Courthouse is a courthouse located at 300 East Ludington Avenue in Ludington, Michigan. It was listed on the National Register of Historic Places in 1988. The first courthouse in Mason County was located in the two-story home of Burr Caswell, who turned over the home to the county in 1856. In 1861 the courthouse was moved to a store building located in the now-vanished village of Little Sauble in the north of the county. In 1873 the county seat was moved to the more centrally located village of Ludington, and a single-story county office building was built. Although this building was enlarged, it was quickly outgrown, and in 1892 voters approved the construction of a new courthouse.