I just spent a few days with a friend who now lives in Grass Valley, California. This is a city just north of Sacramento. I got a wonderful tour of the area, which was built up from the California Gold Rush days in 1850's. Grass Valley, along with the neighboring town of Nevada City, are wonderful gold mining towns to explore. The local mines, the Empire Mine and the North Star Mine, are two of the richest mines in California.
Here's the historic Holbrooke Hotel. I'm guessing there are lots of stories to be told from within these walls.
The tour of Nevada City was very interesting. The streets are narrow, winding, steep, and you wonder if the "gal" in the GPS could really be of help here. She might be in "recalculating" mode most of the time. Some streets didn't even have signs. I think it would take a lot of time to get familiar with getting around on these streets! But the architecture was really great to look at. Lot of Victorian style homes.