Entry No. 69 — the Fort Collins file — filed under: historic

Blue Jay Mine

Dating back to the early 1900s, the Blue Jay Mine was once one of Boulder County's most significant producers of fluorspar. Boulder County acquired the 41-acre property in 2000 to preserve its historic surface features, which include a landmarked hoist house, headframe, and ore bin. Today, the structures are fenced off to protect a large maternity colony of bats, but they remain highly visible from the public trail.

The move: Hike the scenic Blue Jay Mine Open Space trail together to view the historic, landmarked mining structures from behind the safety fence, keeping an eye out for fragments of purple fluorite on the ground.

📍 Before you go The mine is located within Boulder County Open Space and is accessible via a public trail, but the historic buildings are fenced off and closed to the public to protect a sensitive bat maternity colony and ensure visitor safety.

• 📍 Jamestown
• 💸 Free
• ⚡ Low-key
• 🌗 Outdoors

Where: Jamestown, CO 80455, USA

Hours: Added 2026-07-20 — confirm current access before you go.

Plan a visit & invite your people →

Further reading: bouldercounty.gov

last checked: 2026-07-20