National Historic Landmarks in Maryland National Register of Historic Places listings in Howard County, Maryland References External links The Plan for Doughoregan Manor, Howard County gov, 2010 For images, go to the Library of Congress Prints & Photographs Online Catalog and search for Doughoregan Manor. Doughoregan Manor NHL information Preservation Howard County: Manor's Legacy on the Line Preservation Howard County: St. Louis Church , including photo in 1936, at Maryland Historical Trust Benefits of Doughoregan Manor deal cited, Howard County Times Houses completed in 1727 Houses on the National Register of Historic Places in Maryland Howard County, Maryland landmarks National Historic Landmarks in Maryland Carroll family residences African-American history of Howard County, Maryland Plantation houses in Maryland History of slavery in Maryland Houses in Howard County, Maryland Historic American Buildings Survey in Maryland Buildings and structures in Ellicott City, Maryland National Register of Historic Places in Howard County, Maryland Homes of United States Founding Fathers