Historic districts are geographic areas that have a concentration of thematically related historic resources. In general, historic districts have historic significance to the City of Portland, at a minimum, and they are usually also significant at the regional, statewide or national levels. Like historic landmarks, there are two types of historic district: 1) "local" historic districts, designated by the City; and 2) "National Register" districts, those listed on the National Register of Historic Places. Portland has 15 historic districts, primarily located in or near the Central City. All of Portland's historic districts are listed in the National Register.
Properties in historic districts are classified as either "contributing" or "non-contributing" resources, according to standards established by the National Park Service. Contributing resources date from the historic period of significance established for the district. They contribute to the significance and character of the district through their historical associations and/or architectural values. Non-contributing resources are those that, due to date of construction, alterations, or other factors, do not contribute to the district's historic significance or character. The zoning regulations that apply in a historic district generally differ for contributing and noncontributing properties (see the Historic Resource Rules and Benefits page for more information).
Follow the links below to maps of all the historic districts and lists of properties in those districts:
Conservation districts are designated by the City of Portland. As for historic districts, this designation is applied to an area that contains a concentration of related historic resources. The level of historic significance is generally "lower" than for historic districts; they are generally important at the local or neighborhood level rather than at the state, region, or national level. A distinction between "contributing" and "non-contributing" resources is also made in these districts.
Portland has six conservation districts, all located in North and Northeast Portland, created as a result of a neighborhood planning effort, the Albina Community Plan. Documents created as part of this plan include historical background information about each area. See Historic Districts in the Albina Community Plan (1992). Follow the links below to maps of all the conservation districts and lists of properties in those districts.
Finding more information
There are many potential sources of information. For historic districts which are listed in the National Register, the original nomination form is usually the best place to start. Nomination forms contain a wealth of information about the district's physical attributes, historical context, and significant architectural characteristics and historical associations. They also contain bibliographies that point to additional sources. The State Historic Preservation Office maintains copies of all National Register Historic District nominations in Oregon. Their web site includes a list of Oregon properties that have been listed.
District Designation Process
To learn more about the local and National Register district designation processes see the Historic Resources Rules and Benefits page.