The Rockhill Agricultural Historic District is a historic district located north of Pittstown along County Route 513 in a southern triangular portion of Union Township in Hunterdon County, New Jersey. A small part of the district extends into Franklin Township. The district was added to the National Register of Historic Places on April 5, 1984, for its significance in agriculture during the 18th and 19th centuries.
The Bethlehem United Presbyterian Church, now known as the Bethlehem Presbyterian Church, was founded in 1730. The current church building, located in Grandin, New Jersey, was built 1870âÂÂ1871. It replaced the old stone church built 1830âÂÂ1831. Charles Stewart, an officer during the American Revolutionary War, is buried in the church cemetery. The two and one-half story stone Rock Hill Farm was built around 1747.