The Winchester Mystery House in San Jose, California, remains one of the most haunted locations in America. Built by Sarah Winchester, heir to the Winchester rifle fortune, the mansion features 160 rooms, 47 staircases, and doors that open into walls. Paranormal investigators have reported cold spots, disembodied footsteps, and the sound of hammering at night. The house was under continuous construction for 38 years, with workers building around the clock. Many believe Sarah was guided by spirits to keep building. Today, the house welcomes thousands of visitors and investigators annually, with many reporting unexplained phenomena during tours.