"Well No. 4, Pico Canyon Oil Field" was designated a National Historic Landmark on November 13, 1966, on the basis of this 1963 report. It is one of two National Historic Landmarks in the Santa Clarita Valley (the other being Rancho Camulos). The designation covers 850 acres and specifically includes the Pico No. 4 well itself, as well as the remains of abandoned oil derricks, Alex Mentry's 13-room mansion and the Felton schoolhouse.
The designation uses "1880" as the construction date for Mentry's mansion (described herein as "a two-story frame hotel") and the schoolhouse. While 1880 is certainly possible, this is a non-standard date. The Felton School is believed to have been erected in 1885, and we don't really know when the mansion was built, although it is generally believed to have been a bit later than 1880. Writers who use the 1880 date should cite the source ("according to the 1963 National Survey of Historic Sites and Buildings...").
1. State: California
2. Theme: XVII-b — Commerce and Industry
3. Name(s) of Site: Pico Canyon, Well No. "CSO" 4 ("Pico" #4)
4. Approx. Acreage: 850 acres
5. Exact Location: Los Angeles County, 9.6 Mi. north of San Fernando, via U.S. Hwy. 99 & to West of Hwy., or 7 Mi NW of Newhall, via Lyons Ave.
6. Name and Address of Present Owner: Standard Oil Company of California, San Francisco
7. Importance and Description: The birth of California's oil industry occurred in Pico Canyon, which in the '70s and early '80s was the principal oil region of California....
Condition of Site.
Pico Canyon includes about 850 acres of land on which are located the following historical features:
1. Well No. "CSO" 4 ("Pico" #4). The 1876 discovery well of the Newhall Field. This well still produces about one barrel of oil a day and is marked as California Registered State Historical Landmark No. 516.
2. The remains of abandoned oil derricks.
3. A two-story frame hotel, erected in 1880 for use of the oil men and now utilized as a residence.
4. A one-story frame school, erected in 1880, for use of the oil men's children.
These features are little altered and are in a good state of preservation. The area is not opened to the general public because of the high danger of fire to the Canyon.
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