Empire Mine State Historic Park is a historical site located in Grass Valley, California. It was once the largest and richest gold mine in California, producing 5.8 million ounces of gold from 1850 to 1956. Today, it is a popular tourist attraction and one of the premier mining history sites in the US.

Visitors to Empire Mine State Historic Park can take a guided tour of the mine or explore the historic buildings and gardens on their own. The park also offers hiking trails, picnic areas, and a museum with exhibits on the mine's history.

Some of the most popular points of interest at Empire Mine State Historic Park include the main mine yard, the Bourne Cottage, the Assay Office, and the Cottage Gardens. Visitors can also see the mine's original headframe, which stands over 70 feet tall.

The best time of year to visit Empire Mine State Historic Park is in the spring or fall when the weather is mild and the gardens are in bloom. Summertime can be hot and crowded, and the park is closed in the winter months.

Interesting facts about Empire Mine State Historic Park include that it was owned by William Bourn Jr., one of San Francisco's wealthiest men, and that the mine employed over 5,000 people at its peak. The mine also played a significant role in California's early mining history and helped to shape the state's economy.