Over half of California's total gold production came from Grass Valley mines, the biggest and richest being the Empire Mine; it once had 367 miles of shafts and from 1850 to 1956 produced nearly 6 million ounces of gold. Visit not only this but the North Star Mining Museum and the house of Lola Montez - notorious Gold Rush singer and dancer.
Colombia State Historic Park
Most of Colombia's 15,000-strong population left once its mines stopped yielding gold in the 1850s and today it is preserved with much of its mining equipment and buildings still intact. There are Wild West hotels and saloons; old-style stores; a newspaper office; a Wells Fargo office; you can even take a stagecoach ride round town.
Marshall Gold Discovery State Park
It was here in Coloma that James Marshall found the first gold nugget back in 1848, while constructing a sawmill for John Sutter. There's a replica of the mill he was building, plus a Gold Discovery Museum and buildings left abandoned by migrant Chinese miners. You can also pan for gold in the American River.
Volcano, near Jackson, was once a thriving mining town with 8,000 inhabitants. By 1867 most mining had stopped and the present population of around 100 now lives among buildings left over from the mid-19th century - some still functioning, others deserted, or picturesquely ruined and preserved.
It was a story told by a barman in Angels Camp in 1865 that inspired Mark Twain to write 'The Celebrated Jumping Frog of Calaveras County'. In memory of this, there's been a jumping frog contest taking place here every year from 1928. 'The Jumping Frog Jubilee', with plenty else going on besides, takes place in the third week of May.