The Old Stone Fort was built as a High Dutch (German) Reformed church in 1772. It was the third building erected by the congregation of the Palatine German settlement of Fuchs Dorf (Fox Town). Builders chiseled parishioners’ names into the stones. They include many of the early families of the valley.
With the coming of the Revolutionary War, the church was enclosed by a log stockade in 1777.
One of three forts along the Schoharie River, it was named Lower Fort, downstream from Middle and Upper Forts. The stockade initially enclosed a half acre, later enlarged to an acre [0.4 hectare]. There were blockhouses mounting cannons at two corners. Huts were built Along the inside of the walls to shelter local families, the roofs of which served as a firing step for the defenders to shoot over the wall. Initially garrisoned by elements of the 5th NY Continental Regiment, after 1778 Albany County militia and NY State levies rotated the duty. On Oct. 17, 1780, a force of about 800 loyalists and Indians under Col. Sir John Johnson and Mohawk Capt. Joseph Brant raided the valley and briefly attacked the fort before proceeding north toward the Mohawk Valley. A cannonball hole may still be seen in a cornice at the rear of the building.
The stockade was removed in 1785 and the building continued serving as a church until 1844 when the congregation split and built the present Reformed Churches in the village of Schoharie and in Gallupville.
In 1857 the former fort was sold to New York State for $800. At this time the belfry was removed and tower height increased by about nine feet (3 meters). A second floor was installed where there had been a balcony gallery. Through the Civil War and until 1873 it was used as a militia/National Guard armory. Then the state turned it over to Schoharie County for preservation.