US Post Office-Petaluma
Also known as: Petulama Post Office
Approximate location: the National Park Service places this pin arbitrarily within the property, not at a surveyed point (stated accuracy ±12 m).
Why it's listed
Petaluma's main post office, at 120 4th Street, was designed in 1932 and completed in 1933 under the federal government's Supervising Architect's office. Its buff-colored stucco walls, red clay tile lobby roof and rigidly symmetrical facade of five arches reflect a Spanish Colonial Revival approach, with Mediterranean, Spanish Baroque and Art Deco touches. Dark green veined marble columns frame the central entrance, wrought iron scrollwork fills the arches, and terracotta gargoyles sit on the piers. The building was authorized and funded by the 1926 Keyes-Elliot Act and is considered an excellent example of the post offices built under that law. Its central arcade with flanking wings monumentalized the entrance without adding significant cost, and the design bridges 1920s classicism and the leaner Starved Classical style of the 1930s. Later changes include a lobby extension, replaced doors and service counter, and a covered skylight, yet the building retains substantial integrity.
Significance in brief: The nomination argues it is an excellent example of the post office type built under the 1926 Keyes-Elliot Act, which funded federal building programs in California. Its central arcade flanked by wings was a hallmark of late 1920s and early 1930s designs. The style is transitional between 1920s classicism and the Starved Classical style of the 1930s. It is significant at the state level and retains substantial integrity.
Machine-generated summary. This summary was generated by a language model from the official nomination document and has not been reviewed line by line by an editor. It may contain errors. Check the source document before relying on any detail. Source: nomination document (PDF) · National Archives catalog entry. NRHP reference 85000140, listed January 11, 1985. Summary generated October 2026 (model claude-sonnet-5-5, prompt v1.0-2026-10-29, confidence high).
Key facts
| Address | 120 4th St., Petaluma |
|---|---|
| County | Sonoma County |
| Listed | January 11, 1985 |
| Reference number | 85000140 |
| Resource type | Building |
| Period of significance | 1900- |
| Architect / builder | James A. Wetmore; Louis A. Simon, OSA |
| Architectural style | Spanish Colonial Revival, with eclectic Italianate-Mediterranean ornament on a classical box; transitional to Starved Classical |
| Criteria |
|
| Areas of significance | Architecture |
| Level of significance | State |
| Status (as stated in the nomination) | Described as in excellent structural condition and occupied; a mailing platform expansion and a handicap access ramp were under construction at the time of the form. |
| Acreage | 0.8 |
| Coordinates | 38.23180, -122.63776 (NPS GIS) |
What listing means for this property
For a publicly owned building or structure, listing mainly matters when federal funds, permits or licences are involved: projects then go through Section 106 review so effects on the property are considered. Listing also strengthens applications for preservation grants and, for leased income-producing uses, can enable the federal rehabilitation tax credit.
General information, not legal or tax advice. Rules change; confirm with your State Historic Preservation Office or a qualified adviser.
Sources and further reading
- National Park Service, National Register of Historic Places database (snapshot May 2026), reference 85000140.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q14684207
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.