(CNN) — It's super strong, fennel-flavored, as transparent as water -- and in many households across Sardinia it's still produced illegally.
Filu 'e ferru, or "iron wire," is an old drink with a dangerous past and an alcohol concentration of up to 45% that knocks out even those with a high tolerance.
Rosa Maria Scrugli was barely 23 years old when in 1970 she was sent on a work mission to the small town of Santu Lussurgiu, set in the wild Oristano area of western Sardinia amid rocky hills and caves.
For 400 years, this place of barely 2,000 residents has been making a potent filu 'e ferru locally dubbed "abbardente" -- a word deriving from Latin which fittingly means "burning water."
The mayor -- the town's cobbler -- greeted Scrugli at noon with several welcoming shots, but by the time she'd downed the second, she nearly collapsed, falling on top of the mayor who was only a bit tipsy.
"The next thing I knew, someone had dragged me away and I woke up in my hotel room with the worst hangover ever. The mayor also wasn't feeling too well, but he was used to drinking filu 'e ferru. It was my first time, and it was a shock," Scrugli tells CNN.
Santu Lussurgiu is considered the cradle of the oldest Sardinian tradition of "acquavite" -- literally "vine water" in Italian, and indicating a premium alcohol distillate.
A secret code
The villagers have brewed filu 'e ferru for 400 years.
"Acquavite and abbardente are just synonyms for filu 'e ferru, which is a metaphor, part of a secret code invented at a later stage to refer to acquavite in order to escape police controls," says Santu Lussurgiu's only (legal) distiller Carlo Psiche.
It became an "outlaw" drink in the 19th century when Italy's royal house of Savoy introduced levies on alcohol production, kick-starting an illegal trade that in Santu Lussurgiu continues on a mass scale.
Up until a few decades ago police raids were frequent, farmers had to hide bottles of their filu 'e ferru either in some secret place at home or underground in their garden, marking the spot with a piece of iron. Hence the name "iron wire."
In coming up with such a nickname, locals might have also been inspired by the nearby rocky mountain range of volcanic origin called Montiferru -- the "iron hill."
What has always made Santu Lussurgiu's acquavite exceptional, as opposed to those produced in the rest of Sardinia, is that it is distilled from wine, not marc, a spirit made from the residue of the skins and seeds of grapes after the wine has been extracted. It is therefore not a grappa -- Italy's favorite post-meal shot.
Psiche claims his Distillerie Lussurgesi, featuring alembic copper stills used for old-style distillation processes, is the only one among the five filu 'e ferru distilleries in the wider region to use real wine instead of marc, or "vinacce."
Meanwhile, families in the village have been brewing filu 'e ferru at home since the late 16th century, after monks from the local abbey introduced this potent alcoholic distillate in the area.
"At first it was used for its medical and therapeutic properties, particularly for toothache, then people realized it was great as booze, too," says Psiche.
Police raids and secret signals
Santu Lussurgiu is in the hills in the west of Sardinia.
Courtesy Michele Salaris
Everyone in the village still secretly makes abbardente at home. None of them pay taxes on it, except for Psiche, who runs a business.
Nowadays things are less risky than in the past. After all, many Italians brew wine and all sorts of liqueurs at home, and authorities no longer go knocking on people's doors unless they've set up a large-scale business.
Psiche recalls that up until the 1960s, when tax police patrolled the village in search of clandestine producers, people would hurry to hide their bottles and alembics, shouting to each other the emergency code "filu 'e ferru." It was like a curfew signal.
"I was just a kid, but I remember the elders describing the policemen parking their cars in front of the town hall and wandering around hunting like hounds for illegal producers."
Fennel seeds are added to filu 'e ferru to soften the pungent flavor, and given its intense scent, the smell of fennel oozing out from homes occasionally helped the police track down illegal activity.
"There used to be a village messenger whose job was to announce local laws, events and measures by trumpet. When the abbardente raids occurred he'd use another key to warn people," says Psiche.
Italians and foreigners who knew of the secret filu 'e ferru would flock to Santu Lussurgiu to buy entire flasks of it, says Psiche, but they asked too many questions with the risk of exposing producers. So eventually locals decided to go completely underground.
The village had some 40 distilleries by the end of the 1800s, when filu 'e ferru had become a popular drink and was exported across Italy. However, the distilleries were shut in the early 20th century and production became solely "domestic."
Psiche, a former mechanic, decided to recover the old village tradition of acquavite 20 years ago. His abbardente, made with fresh local white grapes, comes in two versions, both aged for at least 12 months.
The clear-as-water abbardente has an intense enveloping taste with a slight dried fruit and almonds flavor, and is diluted with water from a nearby village source. It is aged in steel tanks.
The amber colored abbardente is instead aged in oak barrels. The wood maturation gives it a sweetish flavor reminiscent of honey and homemade bread.
A female affair
Psiche uses traditional copper stills in his distillery.
Psiche's artisan distillery features old distillation objects and an original acquavite bottle from 1860. He has several American clients in Ohio and Chicago, where many villagers migrated.
"Our village has always used wine instead of marc because the vineyards over here tend to over-yield so the best way to avoid any waste was to use the wine to make abbardente," says Psiche.
While men tended to the fields, filu 'e ferru production in Sardinia was a women's business. Wives, daughters and grandmas became experts in distillation. At first, huge pots of copper, traditionally for milk, were used and sealed with flour dough to heat the wine. Later, the ladies turned to copper stills.
Sardinians have a love affair with their "hot water," just as Neapolitans do with coffee.
Even though it is great as an after-dinner digestif, whenever it's toasting time a shot of abbardente works fine.
According to Psiche, it's also a drink with which to observe death: when someone dies it is customary to savor a glass of filu 'e ferru during the midnight wake to honor the deceased.
Filu 'e ferru is as fiery as the Sardinians who keep making it at home, just like their ancestors, sticking to tradition. They believe it can be drunk just like pure water.
One woman from Santu Lussurgiu, who spoke to CNN on condition of anonymity over fear of being busted by authorities, says it's not just for special occasions: "Those who like it drink it at any time of the day, even at breakfast."
Making filu 'e ferru strictly for personal consumption, she uses a huge alembic belonging to her grandparents that has been in the family since the 1960s.
"It takes me half a day to distil the wine, which grows on our land. Other than fennel, I often add absinthe," she said.
The woman says she has now also involved her son in the daily preparation of their homemade filu 'e ferru -- perhaps a sign of changing times that men like Psiche should play a key role in preserving the alcoholic heritage.
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