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Hikes & Events

Assay Office Museum Open House

Assay Office Museum 6352 Fourmile Canyon Dr, Boulder

Stop by the unique Assay Office Museum on this open house day. Learn about assaying, hard rock mining, and the families in the area long ago. Registration not required.

Crepuscular Wildlife

Heil Valley Ranch - Wapiti Trailhead 1188 Geer Canyon Rd., Boulder

Join us as dusk descends and witness the magic of crepuscular wildlife! We'll explore the fascinating world of mountain lions, graceful mule deer, booming nighthawks, and dazzling moths as they come alive after dark. Learn how these animals have adapted to thrive in the twilight hours. This program is perfect for nature enthusiasts of all ages! Registration for most programs begins on the 20th of the month before the event. Registration required. Register Registration is required through Discover Boulder County, Parks & Open Space’s volunteer and event registration system. If you’re new to the system, you'll need to create an account. But it’s easy and we only use your contact information to communicate about events you register for. We will never sell or give your information to a third party.