Historic and conservation districts are geographic areas that have a concentration of thematically related historic resources. In general, historic and conservation districts are collections of historic resources that in and of themselves may not be eligible for individual designation but together convey a significant story.
Properties in historic and conservation districts are classified as either "contributing" or "non-contributing.” Contributing resources were built during the district’s period of historic significance and retain physical integrity from the historic period. Non-contributing resources were built after the district’s period of historic significance or have been too altered to convey physical integrity. Although different historic resource protections apply to contributing and non-contributing resources, the zoning code applies rules across historic and conservation districts to ensure the preservation of their unique qualities.
Historic districts can be designated by the City of Portland or the National Park Service. All locally-designated historic districts have also been listed on the National Register of Historic Places.
Conservation districts are geographic areas that are significant at the neighborhood level and regulated with more flexible historic resource protections than historic districts. All of Portland’s existing conservation districts were created as a result of the 1992 Albina Community Plan.
Details on the process for listing a historic or conservation district can be found on the Historic Resource Designations page.