Entry No. 40 — the Santa Barbara file — filed under: ruins
Asphaltum Mine
Established in the late 1890s by the Alcatraz Asphalt Company, the Asphaltum Mine was a major source of natural bitumen located on the historic Rancho Sisquoc. The company constructed a state-of-the-art liquification plant here, transporting liquefied asphalt through a groundbreaking 30-mile pipeline to a refinery on the Gaviota Coast. Today, the mine is completely abandoned, with no active operations, though it remains a historical geographic landmark on private ranch land.
The story
In the 1890s, the Alcatraz Asphalt Company locked onto a massive deposit of natural bitumen buried beneath the dirt of Rancho Sisquoc. Instead of hauling thick tar out by wagon, they constructed an industrial liquefaction plant directly on the ranch, boiled the raw asphaltum until fluid, and forced it through a 30-mile pipeline cut straight through the hills down to a refinery on the Gaviota Coast.
Between 1890 and 1898, the operation ran as a high-tech engineering experiment dropped into rural cattle country. Once the mine folded, the machinery was abandoned and the pipeline emptied. What remains is a ghost of early industrial infrastructure buried under northern Santa Barbara County ranch land.
What it's like
Do not go hopping cattle fences—the mine site sits deep within Rancho Sisquoc, an active working ranch and vineyard that strictly prohibits trespassing. Your best move is to drive the Foxen Canyon Wine Trail and pull into the Rancho Sisquoc Winery tasting room. Grab a glass of estate red, head out to the picnic grounds, and look out over the rolling, oak-dappled hills knowing that somewhere beneath those placid pastures lies a quiet, abandoned 1890s bitumen shaft.
The move: Take a scenic drive along the Foxen Canyon Wine Trail to visit the nearby Rancho Sisquoc Winery, where you can enjoy estate-grown wines and take in views of the rolling hills that once housed the historic 19th-century mining operations.
📍 Before you go The historic mine site is located deep within the private property of Rancho Sisquoc, a working cattle ranch and vineyard, and is not open to the public.
- 📍 Asphaltum Mine
- 💸 Free
- ⚡ Low-key
- 🌗 Outdoors
Where: Asphaltum Mine, California 93454, USA
Hours: Added 2026-07-20 — confirm current access before you go.
Pair it with
- Benjamin Foxen Adobe Ruins — Four miles down Foxen Canyon Road sit the melted adobe walls of Benjamin Foxen's 1837 home, another piece of 19th-century ranch history left to decay.
- La Purisima Mission — Head southwest into Lompoc to explore a fully reconstructed 19th-century frontier site where you can walk through every unroped room.
- Gaviota Hot Springs (Las Cruces Hot Springs) — Trace the south-bound path toward the Gaviota Coast—where the mine's old pipeline terminated—for a soak in a sulfurous WPA rock basin.
Good to know
Can you hike to the Asphaltum Mine?
No. The historic mine site is on private, working ranch land at Rancho Sisquoc and is off-limits to the public.
How was the mined bitumen transported?
The Alcatraz Asphalt Company liquefied the raw bitumen on-site and pumped it through a 30-mile pipeline down to a coastwise refinery in Gaviota.
Where is the closest place to get a view of the area?
Rancho Sisquoc Winery on Foxen Canyon Road sits on the historic ranch property, allowing you to take in the surrounding landscape from their public tasting area.
Plan a visit & invite your people →
Further reading: edhat.com · goletahistory.com · anyplaceamerica.com · songsofthewilderness.com · independent.com · dailynexus.com
last checked: 2026-07-20