The McCosh Grist Mill is a historic grist mill near Rock Mills in Randolph County, Alabama. The mill was built in the early 1870s, and is the oldest extant stone grist mill in Alabama. It was built by James Eichelburger McCosh, whose grandfather, Jacob Eichelburger, operated earlier mills that were similar to those in his native Pennsylvania. McCosh also owned 500 acres (200 ha) of farmland nearby, and later added a cotton gin to the site. The mill operated until 1958, and was purchased in 1970 by the United States Army Corps of Engineers as part of the West Point Lake reservoir project.