Mansfield Roller Mill (Parke County, Indiana)
Mansion Row Historic District (Floyd County, Indiana)
Maple View Sanitarium (Fayette County, Iowa)
Marathon Oil Service Station (Dallas County, Arkansas)
Mare Island Naval Shipyard (Solano County, California)
Margery Building (Mesa County, Colorado)
Maria Baldwin House (Middlesex County, Massachusetts)
Maria Moore House (Warren County, Kentucky)
Maria Stein Catholic Church and Rectory (Mercer County, Ohio)
Maria Stein Convent (Mercer County, Ohio)
Marine City City Hall (St. Clair County, Michigan)
Marion Courthouse Square Historic District (Perry County, Alabama)
Marion Female Seminary (Perry County, Alabama)
Mark Twain House (Hartford County, Connecticut)
Market Hall and Sheds (Charleston County, South Carolina)
Market House (Providence County, Rhode Island)
Market House Square District (Cumberland County, North Carolina)