When was Hammersly-Strominger House created?

Built by Hammersly, Robert Built c. 1790, and added to in 1835 by Strominger, Michael. Hammersly-Strominger House is a historic home located at Newberry Township, York County, Pennsylvania. It was built in two phases. The first section was built about 1790, and is a  2 1⁄2-story, log structure with a gable roof. A  2 1⁄2-story, gable-roofed, stone section was added in 1835. It features a shed-roofed porch.[2] It was added to the National Register of Historic Places in 1978.