Sarah Winchester began enlarging an eight-room farmhouse in 1886 and kept building, room by room, for decades. At her death in 1922 the house had 160 rooms, 2,000 doors, 10,000 windows and 47 stairways. It opened for tours on June 30, 1923. The legends about ghosts and endless building came largely from newspapers and later promoters; historians describe a capable investor and amateur architect.
The house is a California Historical Landmark (No. 868) and has been on the National Register of Historic Places since 1974. It offers guided mansion tours, and seasonal flashlight tours at night.