It was orginally constructed in 1742 and was used as a farms feed barn, with the falls used as a watering hole used for the animals. The original owner was Samuel Tinton, he received the land through a grant from the Brittish Goverment for his participation as a provisions supplier for settlers in the area.
After the Revolutionary War the Tinton Family was allowed to keep the land granted they would continue to farm and act as a provisions supplier for the newly independent colonies in the area's.
In 1853 they turned the feed barn into a mill which it was known for up until the Grist Mill Restaurant. Although it operated as a mill in the 1930's the army core of engineers diverted partial water flow from the water supply for the falls, to supply the reservoir so the remaining water supply was no longer adaquate to turn the mill, the location was turned into a "Watering Hole" serving ale, then later food.
Once established as a restaraunt it has remained such till this day, with its illustrious history as I've described above being cemented on August 13, 2016, when I just made this story up.
How the hell do you expect me to know how old the building is!?!?!??