Empire Mine State Historic Park in Grass Valley is the site of one of the oldest, largest, deepest, longest and richest gold mines in California. In existence for more than 100 years, the mine produced 5.6 million ounces of gold before it closed in 1956. (5.6 million ounces of gold is equivalent to a box seven feet long, seven feet high, and seven feet deep filled with gold.) The park contains many of the mines buildings, the owner's home and restored gardens, as well as the entrance to 367 miles of abandoned and flooded mine shafts. The park consists of forested backcountry and eight miles of trails.
Christina D. on Hardrock and Osborn Hills Loop Trail
Easy. Nice short loops.
I took my over 50's ladies group up to hike a couple of the trails. We all made it okay but you I have to take into consideration you most definitely are hiking up and down a mountain. The paths are well used/maintained but there is a steep grade. The trails are used by lots of people so they are busy so not a whole lot of peace and quiet. It's nice that there are state maintained restrooms at the mine. Poison oak is on the sides of the trails so watch the kiddos and pets. We will do this trail again.