After falling into disrepair and sitting vacant for more than 50 years, a gristmill in Salem, Indiana, was restored in 2008. Beck's Mill was once a hub of activity and was a vital tool for early settlers. But what is gristmill? A few miles outside of Salem, you'll find an old mill built in the 1800s called Beck's Mill. "Not only did you get your milling done, you picked up your mail. we've got a post office right behind us," said Beck's Mill volunteer Judy Quinlin.