Entry No. 36 — the Monterey file — filed under: ruins
Pogonip Historic Lime Kiln
Tucked away in the redwood forests of the Pogonip Open Space, these crumbling 19th-century stone structures were once used to process limestone into lime for mortar and plaster. Built by industrialist Henry Cowell's crew, the massive kilns are now slowly being reclaimed by the surrounding forest, covered in moss, ferns, and ivy. Today, visitors can view the impressive stone ruins and read an informative historical placard at the site.
The story
Long before Santa Cruz was a surf town, industrialist Henry Cowell ran a heavy timber and lime operation across these hillside forests. His crews built these massive stone kilns in the 19th century to bake quarried limestone into quicklime, supplying the essential mortar and plaster that raised booming California cities. The fires consumed mountains of local redwood timber, baking the stone at brutal temperatures until the operation eventually ran its course and fell quiet.
When the fires went out, the forest moved back in to claim the debt. Today, the hulking masonry structures look less like 19th-century industrial infrastructure and more like ancient temple ruins swallowed by the jungle. Ferns sprout from mortar joints, ivy chokes the arches, and thick green moss mats every square foot of dark stone.
If you know where to look off the main path, the weirdness extends beyond industrial decay. Up the trail network, locals have spent years maintaining quietly added forest anomalies—including a stone floor labyrinth, a hidden fairy rock garden, and a secluded koi pond built directly into the woods.
What it's like
To find the kilns, head into Pogonip Open Space—a dense city preserve bordering the UC Santa Cruz campus—and take the shaded Lime Kiln Trail under thick redwood canopy. The temperature drops noticeably as you approach the towering stone walls and the city's historical placard. After examining the stone arches, keep following the trail higher up to search out the rock garden and labyrinth hidden in the brush. Stick strictly to daytime hours between sunrise and sunset; these deep woods turn dark fast and border long-standing backcountry encampment areas.
The move: Hike the scenic Lime Kiln Trail through the redwoods to admire the moss-covered stone ruins, then continue up the trail to discover the nearby rock labyrinth and fairy rock garden.
📍 Before you go The ruins are located along the publicly accessible Lime Kiln Trail within the Pogonip Open Space, which is open daily to the public from sunrise to sunset.
- 📍 Santa Cruz
- 💸 Free
- ⚡ Low-key
- 🌗 Outdoors
Where: Lime Kiln Trail, Santa Cruz, CA 95060, USA
Hours: Added 2026-07-20 — confirm current access before you go.
Pair it with
- Old Lime Kiln Ruins — Compare Cowell's Pogonip operation to his even larger lime kiln ruins hidden deeper in the woods four miles away at Fall Creek.
- Santa Cruz Surfing Museum — Trade dark industrial forest ruins for ocean views and surf history inside a cliffside memorial lighthouse three miles south.
- Enriquita Mine — Extend the 19th-century industrial ruin hunt by trekking to an abandoned 1850s mercury mine across the ridge in Los Gatos.
Good to know
What were these stone structures actually used for?
Henry Cowell's 19th-century industrial crew used the kilns to burn local limestone into quicklime, which was a critical ingredient for brick mortar and plaster across California.
How do I access the site?
You can reach the kilns on foot via the Lime Kiln Trail inside Pogonip Open Space. The preserve is open daily to the public from sunrise to sunset.
What else is hidden along the trails nearby?
If you follow the trail past the lime kilns, you can discover a hand-assembled rock labyrinth, a fairy rock garden, and the Pogonip koi pond.
Are there restrooms or facilities at the kilns?
No, there are no facilities at the ruins themselves. It is a rustic open-space preserve, so plan ahead and pack out all trash.
Plan a visit & invite your people →
Further reading: sfgate.com · cityofsantacruz.com · hiddenca.com · santacruz.org
last checked: 2026-07-20