Grass Valley is a charming historic Gold Rush town in the Sierra Nevada foothills with a walkable downtown, lively local restaurants and breweries, arts/events, and immediate access to hiking, mountain biking and seasonal skiing—an engaging, comfortable place for multi‑week assignments that rarely feels boring.
If you want occasional big‑city or alpine options, Sacramento (about 57 miles away) and the Lake Tahoe basin are both within easy driving distance.