The remains of the Old Stone Union Church stand in a field next to the Washington Township Historical Museum. A historic sign in the field states that the church was built in 1774, and was "the pastorate of Henry M. Muhlenberg D.D., known as the father of Lutheranism in American." 
There is a cemetery around the church structure which contains the grave of at least one Revolutionary War soldier, Captain John Hager, who died July 17, 1799, age 40. 
For a 2010 Star-Ledger article about the recent partial restoration of the church, click here.
2.^ Information taken from Captain Hager's gravestone
Revolutionary War New Jersey
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Cemetery at the Old Stone Union Church