History loves a monster wrapped in a neat, terrifying myth. For generations, the story of Diogo Alves has been told as a chilling true-crime yarn: a ruthless Spanish immigrant who stalked the towering Águas Livres Aqueduct in Lisbon during the late 1830s, bludgeoning over seventy victims and hurling their bodies into the abyss. Today, his pickled head stares blankly from a glass jar at the University of Lisbon, seemingly serving as hard proof of a legendary reign of terror.
The reality, however, is far more complex than the sensationalist legend. Modern historical analysis shows that the towering body count and the famous aqueduct murders were largely the product of 19th-century folklore, urban panic, and later romanticized retellings. Stripping away the macabre myth reveals a very different criminal reality—and a fascinating look at how historical legends take root.
Who Was Diogo Alves?
Born in Galicia, Spain, around 1810, Diogo Alves migrated to Lisbon while still a young man, seeking work in a city reeling from political and economic instability. Like many Galician immigrants of the era, he found employment on the lower rungs of society, working odd jobs as a servant and a coachman.
By the late 1830s, Alves had drifted away from honest labor. He established a volatile relationship with Maria Gertrudes (known as "Parreirinha"), an innkeeper who ran a local tavern. Surrounding himself with a gang of petty criminals and thieves, Alves transitioned from low-level thievery to organized armed robbery.
The Genesis of the Aqueduct Killer Legend
The core of the popular Diogo Alves legend centers on the Águas Livres Aqueduct, an architectural marvel featuring a pedestrian walkway that crossed high above a valley. Rural farmers and traders returning from Lisbon markets frequently crossed this path with pockets full of cash.
According to the popular narrative, Alves hid along the heights of the aqueduct, robbed lone travelers, and tossed them to their deaths, making the murders look like a wave of suicides. Legend claims that the death toll reached upwards of seventy people before authorities caught on and closed the walkway.
Historical records tell a different story. Legal indictments and court documents from his trial contain zero charges, mentions, or evidence regarding murders on the aqueduct. Archival research shows that deaths and apparent suicides along the structure continued long after Alves was dead and buried. The staggering figure of seventy victims was invented decades later by journalists and writers who conflated mounting suicide statistics with criminal violence.
The Real Crimes and Downfall
Alves didn't need a sprawling aqueduct conspiracy to cement his place in criminal history; his actual convictions were brutal enough. On the night of September 26, 1839, Alves and his gang targeted the home of a doctor named Pedro de Andrade on Rua das Flores in central Lisbon.
What was planned as a robbery devolved into a horrific massacre. The gang murdered the doctor's housekeeper, Maria da Conceição Correia Mourão, along with her two teenage daughters and her adult son. Days later, fearing the household's surviving footman would talk, the gang murdered him as well and disposed of his body.
The botched robbery and subsequent cover-up brought the authorities straight to their door. Alves and his accomplices were arrested, tried, and sentenced to death. In February 1841, Diogo Alves was hanged at the gallows, making him one of the final individuals executed in Portugal prior to the abolition of capital punishment.
The Preserved Head and Phrenology
Following his execution, Alves's body met an unusual fate. During the 19th century, the pseudoscience of phrenology—the belief that psychological attributes and criminal tendencies could be mapped by measuring the bumps on a person's skull—was wildly popular among European academics.
Intrigued by what they viewed as a specimen of pure criminality, medical professionals at the Lisbon Medical-Surgical School severed Alves's head and preserved it in formaldehyde. They hoped to dissect the cranium to find physical markers of a murderer's mind.
The head remains stored at the University of Lisbon's Faculty of Medicine, where it has fueled dark tourism for over a century. Modern historians and museum curators note that even the provenance of the head is shrouded in ambiguity, with no definitive DNA testing or unbroken chain of custody proving beyond a shadow of a doubt that the jar truly holds Diogo Alves.
Common Misconceptions About Diogo Alves
- The Victim Count: Popular media frequently claims he killed over 70 people; however, court records confirm he was convicted of five murders.
- The Aqueduct Conviction: He was never tried, charged, or legally linked to any crimes on the Águas Livres Aqueduct during his lifetime.
- The Execution Date: While often cited as the absolute last person executed in Portugal, capital punishment actually claimed several more lives before its formal abolition decades later.
Frequently Asked Questions
Can the public visit the preserved head of Diogo Alves?
The head is kept in the damp-proof anatomical collection of the Faculty of Medicine at the University of Lisbon. It is restricted to medical professionals and researchers and is rarely opened to the general public, though it occasionally features in special historical exhibitions.
Why did the myth of the aqueduct murders grow so large?
Late 19th and early 20th-century sensationalist journalists, novelists, and early filmmakers found the image of a villain lurking atop a historic landmark far more captivating than a standard home invasion robbery. Over decades of retellings, urban legends merged with true crime until the fiction eclipsed the court transcripts.
Was Portugal's capital punishment system abolished soon after his death?
Alves was executed in 1841. While capital punishment for civil crimes was phased out significantly in the following decades, it was legally abolished in Portugal in 1867, making Alves one of the final wave of executed criminals rather than the absolute last.
