The following list presents the full set of National Register of Historic Places listings in Multnomah County, Oregon. However, please see separate articles for listings in each of Portland's six quadrants.
The Sovereign Hotel was a Portland, Oregon, hotel built in 1923. The nine-story building was added to the United States' National Register of Historic Places on December 2, 1981. Part of the building houses a portion of the Oregon Historical Society's Oregon History Center.
The Ladd Carriage House is a building in downtown Portland, Oregon, at Broadway and Columbia. It is one of the few surviving buildings forming part of the former grand estates which once stood in the downtown core. It is listed on the National Register of Historic Places.
The Hamilton Building is a historic office building in downtown Portland, Oregon. It went through a renovation in 1977, and was listed on National Register of Historic Places in March of that year. It is the neighbor of the Dekum Building, a fellow NRHP listing on Third Avenue.
The Henry Weinhard Brewery complex, also the Cellar Building and Brewhouse and Henry Weinhard's City Brewery, is a former brewery in Portland, Oregon. Since 2000, it has been listed on the National Register of Historic Places. In that same year, construction began to reuse the property as a multi-block, mixed-use development known as the Brewery Blocks.
The Failing Office Building is a building in downtown Portland, Oregon, United States that was listed on the National Register of Historic Places on October 31, 2007. The building was built during the rapid growth in Portland's business district after the Lewis and Clark Centennial Exposition in 1905. It was built with six stories in 1907, with a six-story addition in 1913. It features a reinforced steel-frame structure with facades of yellow brick and glazed terra cotta.
The Portland Hotel was a late-19th-century hotel in Portland, Oregon, United States, that once occupied the city block on which Pioneer Courthouse Square now stands. It closed in 1951 after 61 years of operation.
Whidden & Lewis was an architectural firm based in Portland, Oregon, in the United States, around the beginning of the 20th century, formed by William M. Whidden and Ion Lewis. The partnership was established in 1889. Their residential buildings were mostly in the Colonial Revival style, while their commercial buildings were primarily in the 20th-century classical style. The commercial buildings often featured brick, along with terra cotta ornamentation. Many of their buildings are listed on the National Register of Historic Places (NRHP).
William Marcy Whidden was a founding member of Whidden & Lewis, a prominent architectural firm in Portland, Oregon, United States.
Ion Lewis was a founding member of a Portland architectural firm Whidden & Lewis that was formed around the beginning of the 20th century. The firm was formed with partner William M. Whidden. Their residential buildings were mostly in the Colonial Revival style, while their commercial buildings were primarily in the twentieth-century classical style. The commercial buildings often featured brick, along with terra cotta ornamentation. Many of their buildings are listed on the National Register of Historic Places (NRHP).
The Odd Fellows Building in downtown Portland, Oregon, was built in 1922–1924. It served historically as a clubhouse. It was listed on the National Register of Historic Places in 1980 for its architecture, which is Late Gothic Revival.
The Frigidaire Building or Templeton Building is a building in southeast Portland, Oregon listed on the National Register of Historic Places. The building was designed by William C. Knighton and Leslie D. Howell and completed in 1929 for O.E. (Oscar) Heintz and occupied by Frigidaire until 1934. When prohibition was repealed in 1933, the Oregon Liquor Control Commission was created through Oregon's Knox Bill. OLCC occupied the building once Frigidare left. Later it was occupied by R.J. Templeton, an auto parts distributor.
The First Unitarian Church of Portland is a church building located in downtown Portland, Oregon, listed on the National Register of Historic Places. Located on S.W. 12th Avenue at Salmon Street, it was constructed and opened in 1924.
The M. Lloyd Frank Estate, also known as the Frank Manor House, is an historic building on campus of Lewis & Clark College, in Portland, Oregon, United States. It is listed on the National Register of Historic Places.
The H. Liebes and Company Building is a commercial building located at 625 SW Broadway in southwest Portland, Oregon. It was listed on the National Register of Historic Places on September 12, 1996.
The Postal Building is a building located in downtown Portland, Oregon, that is listed on the National Register of Historic Places. Designed by Whidden & Lewis, it was built in 1900 and is notable for its ornate terra cotta ornament.
The Roosevelt Hotel was a hotel located in downtown Portland, Oregon at 1005 SW Park. It was built in 1924 and is listed on the National Register of Historic Places. In 2000–2001 the building was converted to condominiums.
The Stevens Building is a commercial and office building located in downtown Portland, Oregon, listed on the National Register of Historic Places. The 12-story building was designed by Whidden & Lewis. The design is similar to the Failing Office Building (1907) and Wilcox Building (1911), also by Whidden & Lewis. Construction began in August 1913 and was completed in 1914, with the building opening on May 1, 1914. The total construction cost was $375,000. The building is approximately 152 feet (46 m) tall.
The Charles F. Adams House is a historic house located in northwest Portland, Oregon, United States. It was designed by the eminent firm of Whidden and Lewis, one of a trio of adjacent residences designed by that firm. Built in the Georgian Revival style in 1904 and expanded in 1918, it was extensively restored in 1979. The original owner was Charles Francis Adams (1862–1943), a scion of the family of presidents John Adams and John Quincy Adams, and a prominent Portland banker, art collector, and patron of the Portland Art Museum.
The Whidden–Kerr House and Garden, also known as High Hatch Estate, is a historic property located in the unincorporated communities of Riverwood and Dunthorpe in Multnomah County, Oregon, south of Portland and north of Lake Oswego, Oregon. William M. Whidden of Whidden & Lewis designed the house in 1901, to be his own residence, and it was built the same year. Whidden and his family lived in the house until 1911, when he sold it to businessman Thomas Kerr, Sr. (1896–1925). It later passed to Kerr's son, Thomas Kerr, Jr., and ultimately remained with the Kerr family until 1987.
