Entry No. 38 — the Santa Cruz file — filed under: ruins
Pogonip Historic Lime Kiln
Dating back to the late 19th century, these massive stone kilns were built by industrialist Henry Cowell's workers to process limestone into lime for San Francisco's early buildings. Today, the towering, moss-covered masonry structures stand abandoned in a dense redwood forest, slowly being reclaimed by nature. Visitors can admire the impressive ruins and read an educational placard from the safety of the public trail.
The story
Before San Francisco could assemble its brick-and-mortar skyline in the late 19th century, industrialist Henry Cowell’s workers were burning Santa Cruz mountain limestone inside massive masonry kilns. The quicklime produced here was hauled out to mortar the rising city up north. Once the fires went cold, the industry moved on, leaving towering stone ovens buried deep in what is now Pogonip Open Space.
What you find today along the Lime Kiln Trail looks less like a factory and more like an overgrown ruin swallowed whole by the redwoods. Moss carpets the heavy stone masonry, ferns grow out of mortar joints, and heavy redwood canopies block out most of the sky. Archways that once served as draw holes open into shadowy, empty chambers where heat once blasted continuously.
The kilns aren't the only strange artifact tucked into these woods. If you keep following the trail past the ruins, the redwood forest discloses two more unexpected detours: a hand-arranged rock labyrinth and a quiet, dark forest pond housing live wild koi.
What it's like
The hike along the Lime Kiln Trail takes you under dense redwood canopy straight to the base of the masonry structures. You won't be scrambling inside—a wooden fence rings the kilns to keep people off the crumbling stone, but you can walk right up to the perimeter to inspect the stone draw holes and read the educational placard. The atmosphere is damp, shadowy, and quiet. After taking in the kilns, continue farther along the trail network if you want to seek out the rock stacks and the koi pond. Confirm current trail access with the city before heading out, as park conditions can change.
The move: Hike the scenic Lime Kiln Trail to photograph the moss-draped stone ruins, then continue up the path to explore the nearby whimsical rock labyrinth and peaceful koi pond.
📍 Before you go Located along the Lime Kiln Trail in the publicly accessible Pogonip Open Space, the ruins are fenced off with a wooden barrier to protect their structural integrity, but they are fully visible from the trail.
- 📍 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
- Evergreen Cemetery — Pair these mossy 19th-century industrial ruins with one of California's oldest public cemeteries, another site heavily shaped by forest reclamation.
- Indexical — Contrast the silent, decaying stonework in the redwoods with experimental sound art at this converted leather tannery venue nearby.
- Santa Cruz Mission State Historic Park (Neary-Rodriguez Adobe) — Connect Henry Cowell's 19th-century quicklime operation to an even older layer of Santa Cruz history at the sole surviving Mission Adobe.
- Go Ask Alice — Head into downtown Santa Cruz after your hike to browse loose herbs and house-brewed tinctures in a compact apothecary.
Good to know
Can you walk inside or climb on the kilns?
No. The stone structures are enclosed by a wooden fence to protect their structural integrity and keep hikers safe, though they remain fully visible from the trail.
Where exactly are the ruins located?
They sit along the Lime Kiln Trail within Pogonip Open Space in Santa Cruz.
What else is located on the surrounding trail system?
Higher up the path, you can spot a rock-stack labyrinth and a shaded koi pond hidden among the redwoods.
Plan a visit & invite your people →
Further reading: sfgate.com · weirdca.com · cityofsantacruz.com
last checked: 2026-07-20