Empire Mine State Historic Park

Useful Information

Location:	10791 East Empire St., Grass Valley, CA 95945. Grass Valley California, the heart of the gold country. Route 80 north, in Auburn turn off onto route 49 north, exit Empire Street. (39.207056, -121.047176)
Open:	MAR to OCT daily 10-17. NOV to FEB daily 10-16. Closed 01-JAN, Thanksgiving, 25-DEC. [2026]
Fee:	Adults USD 5, Children (0-5) free. [2026]
Classification:	Gold Mine
Light:	Electric Light
Dimension:	L=590 km
Guided tours:	Mine Yard: D=45 min. Garden Tour: D=1 h. Estate Tour:
Photography:
Accessibility:
Bibliography:
Address:	Empire Mine State Historic Park, 10791 East Empire St., Grass Valley, CA 95945, Tel: +1-530-273-8522.
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then. Please check rates and details directly with the companies in question if you need more recent info.

History

1850	mine opened.
1869	William Bourn Sr. owned controlling interest.
1929	sold to Newmont Mining.
1956	mine closed.
1975	State purchased the surface property as the Empire Mine State Historic Park.
2013	scheduled opening of the underground tour.

Geology

This was the richest hard-rock mine in California producing 165,000 kg of gold all together. The gold is part of a quartz vein in a massif of grey granite. Such veins are hydrothermal depositions formed by the heat of the granite intrusion.

Description

Empire Mine is the oldest, largest, and richest gold mine in California. The Historic Park contains many of the original mine buildings, the owners’ cottage and the restored gardens and grounds. The park has an area of 342 ha and almost 20 km of hiking trails.

The gold was discovered by George Roberts, but he soon sold his interest. Since 1869 William Bourn Sr. owned controlling interest and the family maintained control until it was sold to Newmont Mining in 1929. The mine was closed in 1959 and almost twenty years later in 1975 it was purchased by the State. The Empire Mine State Historic Park was opened, which soon became a popular tourist destination. The main attractions are historical tours of the Bourn Cottage, the mine yard, and the Park museum. The museum shows a scale model of the underground workings of the Empire/Star mine complex. A gold room displays ore samples from local mines. There is also the Assay Office, and an extensive mineral collection. Visitors can see the video entitled Tears from the Sun which explains various gold mining techniques. But all sights are above ground, although there were almost 600 km of abandoned and partly flooded mine shafts.

In the early 2000s the creation of an underground tour was started, called the Underground Tour Project. The California Cultural and Historical Endowment (CCHE) granted the Empire Mine State Historic Park and the Department of Parks & Recreation more than 1.2 million dollars for its completion. An adit was built horizontally through the quartz-laced grey granite, ending at the main shaft. They installed phone, water and electricity in the adit. The plan was that visitors would ride a mine train through this 250 m long tunnel. Dioramas depicting the advancement of hardrock mining techniques over the years were constructed along the tracks, and the train would stop now and then. At the main shaft a so called stope would be visited, a huge cavern created by the upward mining of the quartz vein. But after spending $2.5M and investing almost a decade of work, they found that the steel beams installed to shore up the tunnel were corroding. This was quite unsafe and would take another $1.4M to fix. It seems this killed the entire project, there is still no underground tour.