SCI FI Wire listed "13 real haunted houses you can visit in the U.S.":
The Winchester Mystery House, San Jose, California: "An addled rifle heiress kept building this massive discombobulated Victorian mansion, believing that she would die if the work stopped. Well, she died, and people still report hearing banging doors and rattling windows and seeing her spirit on staircases that lead nowhere—she's probably trying to figure out how to get out of this giant maze."
Source: SCI FI Wire.