Entry No. 71 — the Coeur d'Alene file — filed under: history
Portland Group Mine
The Portland Group Mine is a historic, long-abandoned lead and silver mine located in the Pend d'Oreille mining district near Garfield Bay in Bonner County, Idaho. Dating back to the early 20th century, the site was once part of the region's silver-lead mining boom. Today, the mine is completely inactive, with its old shafts and workings reclaimed by the dense forests of the Idaho Panhandle.
The story
Back during the early 20th-century silver-lead boom, almost every heavily timbered ridge above Lake Pend Oreille had prospectors driving steel into the rock. The Portland Group Mine was one of those raw, workaday claims in the Pend d'Oreille mining district near Garfield Bay. While massive corporate operations grabbed headlines across Shoshone and Bonner counties, small outfits like Portland relied on hand-dug drifts, timber shoring, and relentless optimism that the next round of blasting would strike rich galena and silver veins.
The excitement faded long ago, and nobody stayed behind to clean up. Today, the site is completely inactive, its underground shafts and workings surrendered to decay, rot, and thick cedar-fir forest. The wilderness around Garfield Bay has spent decades reclaiming the hillsides, masking old spoil heaps and leaving unstable subterranean tunnels buried in unmarked terrain. You won't find a polished visitor center or a historic marker out here—just a quiet relic of Idaho's mineral rush being swallowed by the Panhandle.
What it's like
Expect steep, unmarked terrain with no groomed footpaths leading into the workings, along with the distinct possibility of crossing onto private property boundaries. What you get is raw North Idaho backwoods—dense timber, brushy draws, and old underground mine structures that are dangerously unstable and strictly off-limits to enter. For a safer outing with a clear view of the landscape early miners worked, take the scenic drive down to Garfield Bay and hit the nearby Mineral Point Trail for blufftop views over Lake Pend Oreille, keeping your eyes on the forest floor rather than heading underground.
The move: Take a scenic drive to nearby Garfield Bay on Lake Pend Oreille, then hike the Mineral Point Trail to enjoy stunning lake views and appreciate the rugged landscape where historic miners once worked.
📍 Before you go The mine is located on rugged, unmarked terrain near Garfield Bay and may sit on private property; additionally, abandoned underground mine workings are structurally unstable and highly hazardous to enter.
- 📍 Portland Group Mine
- 💸 Free
- ⚡ Low-key
- 🌗 Outdoors
Where: Portland Group Mine, Idaho 83860, USA
Hours: Added 2026-07-20 — confirm current access before you go.
Pair it with
- Conjecture Mine — Pair two historic silver-lead sites across Lake Pend Oreille to see how early 20th-century prospectors tackled North Idaho's ore belts.
- Bellville Mine — Compare how different underground lead and zinc prospects from the region's mining boom have been swallowed by the surrounding forest.
- Silver Leaf Mine — Explore another historic underground silver operation in Bonner County to understand the scale of the area's forgotten hard-rock rush.
- Coeur d'Alene Astronomy Club star parties (Farragut State Park) — Balance a daytime hike around Garfield Bay and mining history with dark-sky stargazing at nearby Farragut State Park.
Good to know
Can I go inside the underground shafts at Portland Group Mine?
No. The abandoned underground workings are structurally unstable, prone to collapses and toxic air, and extremely unsafe to enter.
Where is the mine located?
It sits in rugged, unmarked country near Garfield Bay in Bonner County, Idaho, within the historic Pend d'Oreille mining district.
Is the site open to the public?
The site sits on unmarked, rugged land that may be private property. You need to verify land ownership and confirm current access before attempting to go near the area.
What metals were mined at Portland Group Mine?
The mine operated as a lead and silver prospect during northern Idaho's early 20th-century hard-rock mining boom.
Plan a visit & invite your people →
Further reading: topoquest.com · anyplaceamerica.com · fs.usda.gov
last checked: 2026-07-20