Now they're now opening the doors to their secret palazzos -- for a fee. Guided tours, complete with anecdotes and munchies, now greet guests at luxurious residences once restricted to blue bloods.
Some of the buildings that still house Rome's aristocrats also offer sumptuous rooms for rent, giving guests a taste of the good life.
Canopy beds, silk wallpaper, parquet floors, plush velvet sofas and tables inlaid with onyx and precious stones make this lavish 1500s palace, designed by architect Bartolomeo Ammannati, an elegant treat for guests.
Still owned by the Ruspoli family, whose members became rich as bodyguards to the pope, the palazzo is located in front of the Spanish Steps where the Via dei Condotti and Via del Corso meet.
There are three grand suites available to guests decorated in a 1700s French style, including the room where Emperor Napoleon III grew up. Rates start at €350 per night.
One suite has a library, where a faux wall of books is really a door to a tiny, secret hiding place, like the ones seen in mystery movies.
Princess Giacinta Ruspoli, 27, lives one floor above the rooms for rent with her parents. She has tea with guests and enjoys telling stories of how a Scottish warrior of Charlemagne's fell in love with a Ruspoli beauty, founding the dynasty around 800 AD.
"We want to share everything we have. Our house must not be a shut museum," she said.
Breakfast and meals are served in the terrace garden.
Residenza Ruspoli Bonaparte, www.residenzaruspolibonaparte.com
, Via della Fontanella di Borghese, 56 - 00187 Rome, Tel. +39 3428861007
This 16th-century palazzo is famous for its view of the "Crazy Column," the 42-meter-tall Roman pillar of Marcus Aurelius on Piazza Colonna, close to the Pantheon in the heart of Rome.
Owner Marquis Giuseppe Ferrajoli welcomes guests on guided tours, serving aperitifs and finger foods on the panoramic terrace at the tour's end. Tours start at €16 per person.
Peeping through the windows at the column outside creates an optical illusion.
"The more you get closer to the window, the farther the column looks. The more you step away, the closer it gets, until you can almost grasp it," says Ferrajoli, who inhabits one wing of the palace.
The Ferrajoli family's origins were humble. They were simple accountants until one lucky ancestor, Giuseppe, climbed the social ladder in the 1800s thanks to his loyalty to a prince.
He built a fortune when Pope Pio IX handed him the tobacco monopoly in 1850 to sell tobacco in the entire Papal State, which extended beyond Rome to all of central Italy.
In the 1800s, the palazzo was a hot spot for masked balls, extravagant parties and the horse race along Via del Corso, which today is the Eternal City's thriving shopping district.
Now visitors can see the palazzo's Etruscan columns, floors of multi-colored Venetian mosaics, coffered wooden ceilings, a labyrinth of mirrors and a chimney made of Egyptian marble.
Gloves, slippers and other relics of Pope Pius IX -- part of the Holy Father's gifts to this loyal family -- are showcased behind glass.
Palazzo Ferrajoli, www.palazzoferrajoli.it
, Piazza Colonna 355, Rome, Tel. +39 0669200497
Residenza Principi Ruspoli Cerveteri
For a night or more, you can be the lord of this medieval castle.
The Residenza Principi Ruspoli Cerveteri, built to defend the Vatican in the 1500s, is embedded within the walls of the ancient Etruscan hamlet of Cerveteri, dating back to 800 BC and located at the northern entrance of Rome.
The defensive hamlet was an important "door" to the Eternal City and was guarded by the papal troops of the Ruspoli princes.
Popes and cardinals loved to go hunting in the surrounding reserve, where guests are now taken on guided tours.
There are four deluxe suites with a common dining hall, where a ceiling-high stone fireplace keeps guests warm. The nightly rate per suite starts at €250, and the entire castle can also be rented out (rates available upon request).
The main entrance and halls are decorated with taxidermied animals. Heads with watery bulging eyes of wild boar, deer and gigantic eagles stick out of thick walls, covered in 16th-century tapestries made of delicate grass cloth.
More explicit scenes are depicted in the bedrooms where nobles once slept.
Diana's Room, which is really a suite, has frescoes of triton studs, centaurs, griffins, sensual mermaids and sexually-aroused satyrs and Pans chasing half-naked girls.
Another suite features images of grotesque masks and orgies between gods, sheep and women in bucolic settings. Goats and men embrace each other while Cyclops and Hercules fight.
You also can spot holes in the walls: The Nazis shot at several frescoes during their raids in World War II.
The gem of the castle is the outdoor loggia with arches and decorated columns, perfect for sunset cocktails. Dinner featuring truffle recipes is served by waiters dressed as Medieval trumpeters.
Residenza Principi Ruspoli Cerveteri, www.residenzaprincipiruspolicerveteri.com
, Piazza Santa Maria 12, Cerveteri, Rome, Tel. +39 3428861007
Palazzo Patrizi Montoro
Host Marquis Corso Patrizi Montoro is your personal cicerone through his sumptuous residence near Piazza Navona and the Pantheon, spinning tales about one unfortunate predecessor who was unjustly jailed for six years by Napoleon III.
The Marquis leads tours of his home, which has been in the family since 1642, entertaining guests and serving drinks and munchies at the end of each guided visit.
At the entrance, there's the Patrizi Montoro coat of arms and motto "Sola Fides," which means "By faith alone."
The decor is a collage of different influences. Statues of Greek gods, a Roman sarcophagus and a medieval tower mingle with Renaissance frescoes and masterpieces collected by papal treasurers.
Paintings of moons dot the wall, recalling the crusades and battles fought by warrior ancestors against the Turks.
There's also a gothic-style hall and a bright pistachio-green room with a fake window painted on the wall.
In addition to the tours, private gala dinners and exclusive cocktail evenings can be organized for visitors. Tour and dinner prices are available upon request.
Palazzo Patrizi Montoro, www.palazzopatrizi.it
, Piazza San Luigi dei Francesi, Rome, Tel. +39 0687901173
Tenuta di Pietra Porzia
Grapevines grow on top of Etruscan tombs and cisterns at this 55-hectare wine estate set in Rome's hilly Frascati neighborhood, from which St. Peter's cathedral can be spotted.
Home to a Roman aqueduct built 2,000 years ago, its maze of turf tunnels were later used as a canteen by booze-addicted medieval monks. Today, guests are treated to wine and Pecorino cheese tastings inside the canteen. These tunnels run deep underground throughout the estate.
The family of current owner Count Vittorio Giulini, which dates back to the Renaissance, bought the estate in the 1800s from the monks who built the property in the 1200s and started the wine business.
Giulini takes guests on tours of the estate, where a vineyard and olive groves rise inside the crater of a volcanic lake, Regillo. A fierce battle took place there in the year 496 BC.
Local myths claim the Dioscuri twins Castor and Pollux appeared to avoid bloodshed, and their faces are now on some of the estate's wine labels.
Giulini has turned his family's summer home, a Fascist rationalist-style villa surrounded by sarcophagi, into an inn and restaurant serving locally grown artichoke specialties.
There are four bedrooms in the villa for guests, and another 12 cozy apartments with kitchenettes in an adjacent 1600s yellow farm house. Rates start at €60 for a double room.
Dinner is served in the company of ballad singers who recite old Romanesque poems.
Tenuta di Pietra Porzia, www.tenutadipietraporzia.it
, Via di Pietra Porzia 60, Frascati, Tel. +39 069464392