To create Tennessee whiskey, after distillation and before aging in barrels, the distillate is trickled through a steep layer (in the case of Jack Daniel’s, a 10-foot column) of carefully prepared and selected charcoal made by burning sugar-maple wood. This process is called “mellowing” and sometimes, as in the case of Jack Daniel’s, it can take four to six days for the whiskey to trickle all the way down through the charcoal. The charcoal filtration method is officially known as the Lincoln County Process, named after Lincoln County, Tenn., where the Jack Daniel’s distillery first used it. (Ironically, in 1871 the county’s boundaries were changed, which put Jack Daniel’s distillery in Moore County, an area in which, even today, alcohol cannot be served). This charcoal mellowing is what gives Tennessee whiskey its distinctive rich, sweet taste. There is also another, less obvious but still important factor in Tennessee whiskey—the pure water used in the distillation process.