Santa Paula Hardware Company Block-Union Oil Company
Also known as: Union Oil Company Building; California Oil Museum
Why it's listed
Standing on the corner of Main and Tenth Streets in Santa Paula, this brick and stone commercial building combines one- and two-story sections and is topped by a five-sided cantilevered corner tower with a bell-cast roof. Four slanted bay windows, carved sandstone details, a cast iron ground-floor front and round and segmented arches give it a Queen Anne character with Italianate touches. Completed in 1890 at a cost of about $32,000, it first held a hardware store, a post office and the offices of several oil companies. On October 17, 1890, the Hardison and Stewart, Sespe and Torrey Canon oil companies joined to form the Union Oil Company, and the incorporation papers were signed upstairs. Inside, ten fireplaces each have a different mantle and tile design. Union Oil moved its headquarters to Los Angeles in 1900 but kept the building as a field office, and opened the California Oil Museum on the first floor in 1950.
Significance in brief: It is the birthplace of the Union Oil Company, which was formed in its second-floor offices on October 17, 1890. It is also described as the only commercial Queen Anne style structure in Ventura County surviving from the 1890s with its integrity intact. Key oil figures Lyman Stewart, Wallace Hardison and Thomas Bard were involved in its construction.
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 86002619, listed August 14, 1986. Summary generated October 2026 (model claude-sonnet-5-5, prompt v1.0-2026-10-29, confidence high).
Key facts
| Address | 1003 E. Main St., Santa Paula |
|---|---|
| County | Ventura County |
| Listed | August 14, 1986 |
| Reference number | 86002619 |
| Resource type | Building |
| Period of significance | 1800-1899 |
| Architectural style | Queen Anne, with Italianate influences |
| Areas of significance | Industry, Economics, Architecture |
| Level of significance | State |
| Status (as stated in the nomination) | Occupied and in excellent condition; houses the California Oil Museum and the Ventura Area Production Office, with some minor alterations. |
| Acreage | 0.2 |
| Coordinates | 34.35424, -119.05982 (NPS GIS) |
What listing means for this property
For an income-producing building, listing (individually or as a contributing building in a district) is the gateway to the 20% federal rehabilitation tax credit on qualified rehabilitation costs, often stackable with state credits. Work claiming the credit must follow the Secretary of the Interior's Standards and be approved in advance.
Listing does not restrict a private owner acting without federal money or permits; where federal funding or licensing is involved, Section 106 review applies.
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 86002619.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q7885880
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.