Nevada City makes a good base for the wider Gold Country. Grass Valley, five miles south, has its own historic downtown and the Empire Mine State Historic Park — California's oldest, largest, and richest gold mine, with 367 miles of underground tunnels. Truckee and Lake Tahoe are about 45 miles east on I-80, reachable in an hour.
The Malakoff Diggins are the most compelling day trip from Nevada City itself — 26 miles north on a winding road, the hydraulic mining canyon is one of the strangest and most beautiful landscapes in the Sierra foothills. South Yuba River State Park at Bridgeport is an easier 15-mile drive south, good for swimming and the covered bridge.