Nieland House (Clayton County, Iowa)
Niels Ole Anderson House (Sanpete County, Utah)
Niels P. Hjort House (Sanpete County, Utah)
Niels Petersen House (Maricopa County, Arizona)
Niewerth Building (Carroll County, Indiana)
Nightengale House (Norfolk County, Massachusetts)
Nightengale, Solomon, House (Norfolk County, Massachusetts)
Nightingale--Brown House (Providence County, Rhode Island)
Niles Farmhouse (Madison County, New York)
Niles House (Attala County, Mississippi)
Niles, Louville V., House (Middlesex County, Massachusetts)
Niles, Louville, House (Middlesex County, Massachusetts)
Nils Ahlstrom House (Jackson County, Oregon)
Nils Skumsrud House (Vernon County, Wisconsin)
Nimocks House (Cumberland County, North Carolina)
Nimocks House (Lorain County, Ohio)
Nimrod Ross House (Lancaster County, Nebraska)
Nine Hearths (Warren County, Kentucky)
Nishnabotna Ferry House (Cass County, Iowa)
Nissen Building (Forsyth County, North Carolina)
Nixon Homestead (Chautauqua County, New York)
Noah and Hannah Hadley Kellum House (Hendricks County, Indiana)
Noah Edward Edgerton House (Johnston County, North Carolina)
Noah McCarn House (Stone County, Arkansas)
Noah Moore House (Clarke County, Mississippi)
Noah Odell House (Adams County, Iowa)
Noah P. Ward House (Douglas County, Minnesota)
Noble Cottage (Calhoun County, Alabama)
Noble Hall (Lee County, Alabama)
A historic Greek Revival style plantation house in Auburn, Alabama.
Noble Judah Estate (Lake County, Illinois)
Noble--McCaa--Butler House (Calhoun County, Alabama)
Noble-Kendall House (Monroe County, Iowa)
Noble-Seymour-Crippen House (Cook County, Illinois)
Nock House (Jefferson County, Kentucky)
Noel Owen Neal House (Howard County, Arkansas)
Noftzger-Adams House (Wabash County, Indiana)
Nola Kitterman House (Carter County, Missouri)
Nolan House (San Miguel County, New Mexico)
Nolte--Rooney House (Brewster County, Texas)
Nonnenmacher House (Calhoun County, Alabama)
Nook, The (York County, Pennsylvania)
Noonan--Norblad House (Clatsop County, Oregon)
Norburn Terrace (Wake County, North Carolina)
Norby House (Sanders County, Montana)
Norcross Brothers Houses (Worcester County, Massachusetts)
Nordica Homestead (Franklin County, Maine)
Nordlund House (Denver County, Colorado)
Norman and Florence B. Carmichael House (San Diego County, California)
Norman Apartment Building (Polk County, Iowa)
Norman B. Streeter Homestead (Custer County, South Dakota)
Norman Brimhall House (Navajo County, Arizona)
Norman Dewey Perry House (Delaware County, Ohio)
Norman Francis Butler House (Walla Walla County, Washington)
Norman Tromanhauser House (Jackson County, Missouri)
Norman's Retreat (Anne Arundel County, Maryland)
Normand House (Chittenden County, Vermont)
Normandy Grange (Putnam County, New York)
Normandy Park (Morris County, New Jersey)
Norris House (Santa Clara County, California)
Norris Miller House (Winneshiek County, Iowa)
Norris Staples House (Clatsop County, Oregon)
Norris-Stirling House (Harford County, Maryland)
North Bend (Charles City County, Virginia)
North Bend (Pointe Coupee Parish, Louisiana)
North Carolina Executive Mansion (Wake County, North Carolina)
North Fork Guard Station No. 1142 (Lewis County, Washington)
North Manor Apartments (Hinds County, Mississippi)
North Mansion and Tenant House (Schenectady County, New York)
North Wales (Fauquier County, Virginia)
North Washington Avenue Workers' House (Rockingham County, North Carolina)
Northcutt House (Gregg County, Texas)
Northcutt Plantation (Warren County, Tennessee)
Northington--Beach House (Montgomery County, Tennessee)
Northrup House (Allen County, Kansas)
Northrup--Gilbert House (Oswego County, New York)
Northside Historic Residential District (Fayette County, Kentucky)
Northup, Stephen, House (Washington County, Rhode Island)
Northwest Company Post (Pine County, Minnesota)
Norton House (Yuma County, Arizona)
Norton House (New Haven County, Connecticut)
Norton House (Bristol County, Massachusetts)
Norton House (Palm Beach County, Florida)
Norton House Historic District (Cumberland County, Maine)
Norton, Charles H., House (Hartford County, Connecticut)
Norton, William F., House (Franklin County, Maine)
Norton-Burnham House (Jefferson County, New York)
Nortonia Boarding House (Washoe County, Nevada)
Norumbega (Knox County, Maine)
Norumbega Carriage House (Knox County, Maine)
Norway Township Stone House (Fillmore County, Minnesota)
Norwegian Buildings at Heg Park (Racine County, Wisconsin)
Outdoor museum of Norwegian heritage of the area
Norwell Residence (Hamilton County, Ohio)
Norwood (Powhatan County, Virginia)
Norwood (Clarke County, Virginia)
Norwood House (Sussex County, Delaware)
Norwood, Andrew S., House (New York County, New York)
Norwood--Hyatt House (Essex County, Massachusetts)
Notleymere (Madison County, New York)
Noto House (Brazos County, Texas)
Nottoway Plantation House (Iberville Parish, Louisiana)
Noves, Charles W., House (Middlesex County, Massachusetts)
Nowack House (Sheboygan County, Wisconsin)
The first home built in Random Lake.
Nowak, Dr. John J., House (Erie County, New York)
Nowell-Mayerburg-Oliver House (Johnston County, North Carolina)
Nowlan-Dietrich House (Adams County, Nebraska)
Nowland House (Tioga County, New York)
Nowland, J. Martin, House (Norfolk County, Massachusetts)
Noxontown (New Castle County, Delaware)
Noyes Cottage (Franklin County, New York)
Noyes Mansion (Napa County, California)
Noyes, J.A., House (Middlesex County, Massachusetts)
Noyes, James, House (Essex County, Massachusetts)
Noyes--Parris House (Middlesex County, Massachusetts)
Nuckolls House (Pottawatomie County, Oklahoma)
Nuckolls-Jefferies House (Cherokee County, South Carolina)
Historic home south of Gaffney, SC
Nugent's Crossroad Historic District (Woodford County, Kentucky)
Nuits (Westchester County, New York)
Null House (Baltimore, Maryland)
Numertia Plantation (Orangeburg County, South Carolina)
Nun's Green (Worcester County, Maryland)
Nurre-Royston House (Hamilton County, Ohio)
Nut Grove (Albany County, New York)
Nutting Homestead, The (Oxford County, Maine)
Nutwood (Troup County, Georgia)
Nutwood Place (Champaign County, Ohio)
Nyberg--Swanson House (Broward County, Florida)
Nye House (Dodge County, Nebraska)
Nye, Benjamin, Homestead (Barnstable County, Massachusetts)
Nye, Elnathan, House (Barnstable County, Massachusetts)
O'Bannon Homestead (Cass County, Missouri)
O'Bier House (Webster Parish, Louisiana)
O'Blenis House (Bergen County, New Jersey)
O'Connor House (Pembina County, North Dakota)
O'Dea House (Prince George's County, Maryland)
O'Dell House (Cocke County, Tennessee)
O'Donnell Building (Vanderburgh County, Indiana)
O'Donnell House (Sumter County, South Carolina)
O'Donohue, C. A., House (Suffolk County, New York)
O'Kane--Jacobs House (Franklin County, Arkansas)
O. A. E. Blyberg House (Otter Tail County, Minnesota)
O. Arthur Kirkman House and Outbuildings (Guilford County, North Carolina)
O. B. McFadden House (Lewis County, Washington)
O. B. Sims House (Ellis County, Texas)
O. C. Barber Creamery (Summit County, Ohio)
O. C. Sarles House (Traill County, North Dakota)
O. D. and Ada Dillingham House (Taylor County, Texas)
O. E. Payne House (Lucas County, Iowa)
O. E. Rolvaag House (Rice County, Minnesota)
O. E. Walker House (Mohave County, Arizona)
O. F. and Mary Prigden House (DeWitt County, Texas)
O. F. Short House (Ada County, Idaho)
O. J. Daniels House (Jerome County, Idaho)
O. K. Palmer House (Lewis County, Washington)
O. L. and Josephine Morgan House (Jefferson County, Washington)
O. L. Dunaway House (Faulkner County, Arkansas)
O. L. Price House (Multnomah County, Oregon)
O. P. Wickham House (Pottawattamie County, Iowa)
O. T. Baker House (Lorain County, Ohio)
O. W. Getchell House (Mendocino County, California)
O.B. Grant House (Elk County, Pennsylvania)
O.F. and Lulu E. Fryer House (Jefferson County, Iowa)
O.J. Gendron Ranch (Yakima County, Washington)
O.W. Francis House (Jewell County, Kansas)
Oak Alley Plantation (St. James Parish, Louisiana)
Oak Crest (Isle of Wight County, Virginia)
Oak Dell (Morris County, New Jersey)
Oak Forest (Hanover County, Virginia)
Oak Glen (Newport County, Rhode Island)
Oak Grove (Cumberland County, North Carolina)
Oak Grove (Hampton County, South Carolina)
Oak Grove (Jefferson County, Mississippi)
Oak Grove (Charles County, Maryland)
Oak Grove (Northampton County, Virginia)
Oak Grove (Campbell County, Virginia)
Oak Hill (Fairfax County, Virginia)
Oak Hill (Loudoun County, Virginia)
Oak Hill (Ross County, Ohio)
Oak Hill (Fauquier County, Virginia)
Oak Hill (Marshall County, Kentucky)
Oak Hill (Colonial Heights, Virginia)
Oak Hill (Columbia County, New York)
Oak Hill (Cumberland County, Virginia)
Oak Hill Cottage (Richland County, Ohio)
Oak Hill Estate (Fayette County, Pennsylvania)
Oak Island (Charleston County, South Carolina)
Oak Knoll (Middlesex County, Massachusetts)
Oak Lawn (Amherst County, Virginia)
Oak Lawn (Caroline County, Maryland)
Oak Top (Montgomery County, Tennessee)
Oak Tree Cottage (Calhoun County, Alabama)
Oakcliff (Saratoga County, New York)
Oakdale (Chester County, Pennsylvania)
Oakdale Cotton Mill Village (Guilford County, North Carolina)
Oakdene (Staunton, Virginia)
Oakdene Place (Floyd County, Georgia)
Oakes Estate (Essex County, New Jersey)