Nevada county has a few roadside attractions that are unique and fun to visit:
Grass Valley robot
This Tin Man and Tin Woman in Nevada City play Wizard of Oz music when you push his bellybutton.
Rough and Ready has an entire mini town dedicated to Gold Mining history.
More from Rough and Ready
Clark's in Nevada City
Old Shell station in Penn Valley (Bridgeport)
If you like old shacks and cabins, then check out the Malakoff Diggins State Historic Park in Nevada City, California. The park is the location of an 1800's gold mining town and what is left is a mini ghost town.
My first trip to this park was last year in the middle of summer. When I decided to make my 2nd trip to the Malakoff Diggins park, I didn't realize it would be 1 to 2 feet deep in snow, but that really made for some interesting images.
If you visit the park, you will find an old cemetery, historic church, lake, hiking locations and you can take guided tours of some old general stores.