Sonoma County Historic Landmarks are historic resources that the Landmarks Commission has determined to be significant based on local, state, and federal criteria.

A historic resource can be a building, a structure, a district, a site, an object, or a record. Typically a historic resource is defined as a building, a structure, or a district. In Sonoma County, Historic Landmarks are mainly buildings. Historic Landmark properties are typically zoned "Historic District" (HD).

Sonoma County has about 190 Historic Landmarks. Most of the Historic Landmarks were designated between the mid-1970s to mid-1980s. Additional Historic Landmarks will be designated in the future under the County’s Historic Preservation Program.

Search for Historic Landmarks by Location or Name

A multi-parcel Historic District is a specific area of the County in which there is a significant concentration or continuity of historic sites, buildings, structures, and objects of historic merit or which represent an historic theme important to Sonoma County, the State of California, or the nation. Each of the existing five multi-parcel Historic Districts have also been designated as a County Landmark.

The purpose of a Historic District is to preserve the historic character and integrity of the exterior of existing structures and regulate the design of the exterior of new structures. This is accomplished through "Historic District" (HD) Zoning of all parcels in the District and approval of a Historic Design Review Permit that complies with the applicable Historic District Design Guidelines for that area. Within a Historic District, structures are determined to be “contributing” or “non-contributing” to the historic significance with different design criteria for each category.

The purpose of HD Zoning is to preserve the historical character of existing structures in a multi-parcel Historic District. HD Zoning requires that the Landmarks Commission review the design of alterations to the exterior of an existing structure or construction of a new structure. Review of new structures by the Commission includes applying the pertinent Historic District Design Guidelines and ensuring that the design of new development is compatible with the historic character of existing structures in the District.

Sonoma County has five multi-parcel Historic Districts – Bodega, Duncans Mills, Freestone, Occidental, and Penngrove.

Bodega Historic District

The County adopted Ordinance No. 3217 establishing the Bodega Historic District on October 31, 1983, and designated it as County Landmark #136. The boundary of the Bodega Historic District (PDF: 168 kB) encompasses primarily the downtown section of Bodega, along both sides of Bodega Highway from about Bodega Calvary Cemetery northeast to about Salmon Creek, including the north and west sides of Bodega Lane.

Properties within these boundaries are subject to the Bodega Historic District Survey and Design Guidelines (PDF: 7.56 MB).

Duncans Mills Historic District

The County adopted Ordinance No. 2949 establishing the Duncans Mills Historic District on March 2, 1982, and designating it as County Landmark #139. The boundary of the Duncans Mills Historic District (PDF: 171 kB) encompasses the area on the west side of State Highway 116 from the intersection with Moscow Road to about 1,500 feet northwest; and along the east and west sides of State Highway 116 from the intersection with Moscow Road to about 700 feet southwest.

Properties within these boundaries are subject to the Duncans Mills Historic District Design Guidelines (PDF: 6.39 MB).

Freestone Historic District

The County adopted Ordinance No. 1849 establishing the Freestone Historic District on December 17, 1974, and designating it as County Landmark #1. The boundary of the Freestone Historic District (PDF: 171 kB) encompasses primarily the downtown section of Freestone along Bohemian Highway from Bodega Road to the northern limits of town. Five buildings in the Freestone Historic District are designated as Historic Landmarks: an 1867 Greek Revival Schoolhouse, 1872 Greek Revival Hotel, 1876 Italianate General Store, and two Greek Revival private residences.

The "Design Review Policy Guidelines for the Freestone Historic District" were first adopted on November 21, 1974 subsequent to a petition in 1973 from 22 Freestone property owners to establish an Historic District.

Properties within these boundaries are subject to the Freestone Historic District Design Guidelines (PDF: 5.96 MB).

Occidental Historic District

The County adopted Ordinance No. 2611 establishing the Occidental Historic District on March 4, 1980, and designating it as County Landmark #137. The boundary of the Occidental Historic District (PDF: 184 kB) encompasses generally downtown Occidental, the east and west sides of both Bohemian Highway and Main Street between 1st Street and Graton Road; and extends along the west side of Bohemian Highway from the intersection with Graton Road to about 1000 feet northwest, and along both sides of Coleman Valley Road from the intersection with Bohemian Highway to about 400 feet northwest.

Properties within these boundaries are subject to the Occidental Historic District Design Guidelines (PDF: 4.91 MB).

Penngrove Historic District

The County adopted Ordinance No. 3273 adopting the Penngrove Specific Plan and establishing the Penngrove Historic District on April 10, 1984, and designating it as County Landmark #138. The boundary of the Penngrove Historic District (PDF: 185 kB) encompasses generally the east and west sides of Main Street from the intersection with Old Redwood Highway to Adobe Road. In two locations, the Historic District is only on the west side of Main Street.

Properties within the Penngrove Historic District boundaries are subject to the Penngrove Main Street Design Guidelines (PDF: 3.41 MB).

Glen Ellen

The boundary of the Glen Ellen area subject to design guidelines (PDF: 266 kB) encompasses an area on the east and west sides of Arnold Drive from about Sonoma Creek to Arroyada Road; and both sides of Warm Springs Road.

On November 14, 1990 the Board of Supervisors adopted Ordinance No. 4297 establishing the Glen Ellen Development and Design Guidelines. The Guidelines represent revised goals, objectives, policies, and design guidelines contained in previous versions of the Glen Ellen Town Plan.

Properties within these boundaries are subject to the Glen Ellen Design Guidelines (PDF: 735 kB). A Historic Context Statement was prepared in 2013 to provide additional historical information relevant to the design of projects in Glen Ellen.

Russian River Corridor

The boundary of the Russian River Corridor area (PDF: 235 kB) extends along the Russian River from Monte Rio to Rio Nido. The Sonoma County Community Development Commission’s Russian River Redevelopment Oversight Committee prepared design guidelines for the area which address historic resources and preservation. The Board adopted the Russian River Corridor Design Guidelines on December 14, 2010.

Properties within these boundaries are subject to the Russian River Corridor Design Guidelines (PDF).

1. Historic Resource Survey and Evaluation Report

   A qualifying architectural historian, historic architect, or historian conducts an historic resource survey and evaluation of the property(ies) and prepares a report. The report includes an analysis of whether the property(ies) is a significant historic resource and meets the Criteria for Designation of Historic Landmarks and/or Historic District (HD) zoning.

   For more information:

   • Historic Resource Inventory, Surveys, & Evaluations
   • Criteria for Designation of Historic Landmarks (County)
   • Historic District (HD) Combining Zone
   • California Register of Historical Resources – Eligibility Criteria
   • National Register of Historic Places – Eligibility Criteria

2. Submittal of Application Materials

   A planning application for a Level 1 Zoning Change to add “Historic District” (HD) Zoning to the property, indemnification agreement, and the historic resource survey and evaluation are submitted to Permit Sonoma. Fees during Fiscal Year 2015-2016 were $1,869.00 (Project Review Fee Schedule Fee Items 1155, 0140, 1052. Fees change annually on July 1.).

   The following forms are required:

   • PJR-001 Planning Application (PDF)
   • PJR-011 Indemnification Agreement (PDF)
   • PJR-034 Zone Change (PDF)

3. Landmarks Commission Public Hearing

   At a public hearing the Landmarks Commission determines whether the property is a significant historic resource and qualifies as a Historic Landmark and for HD Zoning. To make that decision the Commission uses both the Historic Resource Survey and Evaluation Report and its expertise.

   For multi-parcel areas, the Landmarks Commission determines which parcels are included in the Historic District, based on the purpose of the Historic District Combining Zone Chapter 26 Zoning, Article 68 Historic District and the conclusions of the Historic Resource Survey and Evaluation Report. Design guidelines based on the design and architectural characteristics of the buildings are established as a part of the designation of multi-parcel Historic Districts.

   The Commission makes a recommendation to the Planning Commission to either approve or deny designation of the property or area as a Historic Landmark with HD Zoning.

4. Planning Commission and Board of Supervisors Public Hearings

   At a public hearing the Planning Commission takes comments from the public about designation of the property as a Historic Landmark with HD Zoning. The Commission makes a recommendation to the Board. The application proceeds to the Board of Supervisors to consider recommendations of the Landmarks Commission and Planning Commission as well as comments from the public and property owner. The Board makes the final decision.

5. Historic District Zoning

   Historic District (HD) Zoning and Landmark Designation is added to the property if the Board of Supervisors has given approval.