The Lahr Farm is an historic home and farm complex that is located in Warwick Township, Chester County, Pennsylvania. It was originally owned by a wealthy Quaker ironmaster William Branson and part of his Reading Furnace estate.
It was added to the National Register of Historic Places in 1979.
The farm has three contributing buildings; the main house, bank barn, and wash hour or latchen. The house is a -story, four-bay by two-bay, fieldstone dwelling with a gable roof. The farm was inherited by Branon's grandson a wealthy ironmaster Samuel Van Leer. The Van Leer Family's original surname spelling was Von Lahr. The farm remained in the Lahr family from 1834 to 1938.