(CNN) - There's an odd sight just outside downtown San Jose, California's "capital of Silicon Valley."
It's not a convoy of self-driving cars or a brigade of AI robots, but an extravagant, four-story, gabled and turreted Victorian mansion said to be "the most haunted in America."
Winchester Mystery House has loomed large in the imaginations of San Jose locals ever since it was built in 1884. But it's about to draw international travel attention thanks to the upcoming release of "Winchester," a horror movie starring Helen Mirren. The Oscar winner portrays Sarah Winchester, who it's said designed the eccentric home to bamboozle ghosts.
Stealing a peek inside the house isn't confined to the theater, though -- you can easily visit yourself.
The house, a sprawling puzzle of carnival funhouse-esque quirks, perplexes mere mortals as much as malevolent spirits.
Look out for staircases that lead to ceilings; windows set into floors; a door that opens onto a 12-foot drop. (Guides nickname this room "the mother-in-law suite.")
Eerie motifs abound: the number 13 appears everywhere (ceilings with 13 panels; 13 coat hooks in the "seance room". There are also many decorative spider-web patterns -- people believed the latter would bring good luck at the time.
Just as extraordinary is its sheer size: what started as a two-story farmhouse was transformed by Sarah into a seven-story, castle-like residence, with 160 rooms, 47 fireplaces and 10,000 panes of glass.
Sarah could build such a lavish abode because she was heiress to the Winchester rifle fortune. After her husband, William Wirt Winchester, passed, she received an inheritance of $1,000 a day. (The average daily wage back then was $1.50.)
Legend has it, however, the widow believed herself haunted by the spirits of those killed by Winchester rifles.
Inside the house
Whatever the truth, a tour of the mansion is packed with strange insights and intriguing theories.
Visitors will walk narrow, zig-zagging staircases, spot curiosities like upside-down pillars and cupboards a half-inch deep, and even see rooms damaged by the deadly 1906 San Francisco earthquake (which also removed the house's fifth, sixth and seventh floors).
But of all the enduring mysteries surrounding Winchester, perhaps Sarah is the biggest. As Mariah Kampschafer, who has worked as a guide at the house since 2012, admits, most tales about Sarah and her home are conjecture.
There is little in the way of hard facts known about Sarah. She could have been trying to outrun the supernatural, but she also could just have been a really, really bad architect.
Personally, Kampschafer thinks Sarah gets a bad rap. "There's this popular conception she was crazy, but spiritualism and seances and whatnot were really normal at the time," she points out.
Another guide, Mario Ramirez, says many people assume Sarah was a recluse, but insists: "She was actually one of the top socialites in the area."
Choosing a tour
The house appeals to everyone from paranormal fans to architecture nerds and offers tours to match.
The annual Halloween Candlelight tour and the Friday the 13th Flashlight tour are conducted at night, featuring ghost stories recounted by former employees and guests. Ticket prices vary, but expect to pay around $49.
The standard Mansion tour, 65 minutes, focuses on historical and factual details, including Winchester's spooky lore. Tickets cost $39, with a small discount for seniors. Admission is $20 for children aged 6-12.
The Explore More tour can be tacked on to the Mansion tour for an extra $10, and lasts about an hour.
Ticket-holders are taken into unfinished rooms never before seen by the public, including the "witch's cap" turret -- also believed to have been a seance room -- that Houdini visited to disprove rumors about the house. ("He left with more questions than answers," according to guide Melissa August).
Explore More is slated to expire in February, but Kampschafer says demand has been so high, it may be extended. Note it is not suitable for children aged 10 and under, and visitors will need to wear a hard hat (provided).
Did you know?
Even the tour guides believe the house is haunted -- but they say the ghosts are friendly.
On the Explore More tour, August shows the basement where a man pushing a wheelbarrow to the coal chute is often seen: "He always tips his hat," she says.
The estate also has two small museums, included in the ticket price. One exhibits Winchester rifles through the ages, while the other displays antique products marketed by the Winchester brand (spot the "gun smoke" cologne).
Where to eat
The property's on-site cafe serves simple burgers, wraps, salads and the like, as well as coffee and tea.
If you don't happen to be a tech billionaire, San Jose's Michelin-starred Adega may be off the cards (though it's a historical landmark itself, as the first West Coast Portuguese restaurant to win the accolade). But it's perfect if you feel like a splurge.
Local favorite Smoking Pig BBQ is a 10-minute drive, tucked into suburban San Jose. The restaurant has a parking lot and is always buzzy, with sports on the TV and kitchen paper at every table -- if you eat here right, you'll get messy. Make sure to try all four types of house barbecue sauce.
Planning your visit
Winchester Mystery House is open every day except Christmas Day. Hours are 9am to 7pm from Memorial Day (the last Monday in May) to Labor Day (the first Monday in September), and 9am to 5pm from Labor Day to Memorial Day.
The best time to visit is January to March, when crowds are smaller. Mornings between 10am to 11am are quietest -- if you're lucky, you could snag a tour to yourself.
Note the house is not wheelchair accessible, and service dogs are the only animals permitted entry. Photography is not allowed inside the house.
Winchester is located just off the I-280 and I-880 highways; two free parking lots are provided. San Jose Diridon station, the last stop on the Caltrain route between San Francisco and Silicon Valley, is a 10-minute cab ride away. The house is also a 10-minute drive from San Jose International Airport.