Hidden Valley Farm is a historic home and farm complex located at Baldwin, Harford County, Maryland, United States. It consists of a mid-19th century vernacular Greek Revival brick farmhouse with several auxiliary structures. The house is a three-story, rectangular brick dwelling with a gable roof, with a two-story wing. The house features square-columned one-story porches across the façade and both sides of the wing. Also on the property are a mid-19th century barn, summer kitchen, and smokehouse, and later wood shed and garage. Hidden Valley Farm was listed on the National Register of Historic Places in 1983.