Simon Cameron House, also known as John Harris Mansion and the Harris-Cameron Mansion is a site in Harrisburg, Pennsylvania. The structure is one of the oldest buildings in Harrisburg and has undergone numerous additions and significant renovations since it was first constructed in 1766. The house and family items were donated to the Historical Society of Dauphin County in 1941. The mansion was declared a National Historic Landmark in 1975. It is located in the Harrisburg Historic District.