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Who Was Diogo Alves, and How Did His Head End up in a Jar?

Head of Diogo Alves

Head of Diogo Alves

Portugal's First Serial Killer

No need to wait for Halloween—let's talk about a real-life horror story. After all, reality can sometimes be more frightening than any ghost story you can tell.

Diogo Alves has the infamous distinction of being Portugal's first serial killer. He carried out his murderous deeds in a short span of years in the mid-nineteenth century.

However, it was not only his crimes that make him known today. It's what happened after his death.

Following his execution, he became an oddity, an exhibit beyond death. Soon after he was hanged, scientists chose to have his head preserved in a jar. His well-preserved head could still be seen today at the University of Lisbon, where its lifeless stare terrifies visitors to this day.

Sketch of Alves with his head still attached.

Sketch of Alves with his head still attached.

Who Was Diogo Alves?

Born in 1810 to a peasant family in Galicia, Spain, Diogo Alves left home at the age of 19 to work in Lisbon, Portugal. Because of his young age, he started working as a servant for wealthy families. Eventually, after changing jobs, he started gambling and drinking. He also had a lover, an innkeeper named Palhava Maria Gertrudes.

It is believed that it was through this connection to the innkeeper that Diogo found his victims. Eventually, he killed 70 people between 1836 and 1840.

By stealing and falsifying keys, Diogo was able to gain access to the Reservato de Mae Aguas das Amoreiras, an underground gallery that led to the Aquedato das Aguas Livres, his preferred site of murder.

His victims were poor passersby. After robbing them, Diogo blindfolded his hapless victims, dragged them to the top of the aqueduct, and threw them off. A 65-meter drop ensured instant death. It earned Diogo the nickname, “the Aqueduct Murderer.” (His first nickname was "Pacanda," meaning "blow," referring to an accident earlier in his life when he fell from a horse and hit his head.)

Aquedito das Aguas Livres

Aquedito das Aguas Livres

Scene of the Crime: Aquedito das Aguas Livres

Diogo's preferred place of murder was the Aquedito das Aguas Livres, an historic aqueduct in Lisbon. The main course covers 18 kilometers, but the whole network extends up to 58 kilometers.

The aqueduct was built by King John V to provide drinking water to Lisbon. Under the direction of the Italian Architect Antonio Canevari, construction started in 1731. In 1732, a group of Portuguese architects and engineers replaced Canevari. The structure was still unfinished in 1748, but it began to bring water to the city of Lisbon. It survived the 1755 Lisbon earthquake, which devastated much of the city.

It was this aqueduct that became Diogo Alves's killing ground. It might come as a surprise to most people that 70 murders in the same location could have evaded police detection. At the time, however, the country was in the midst of an economic and political crisis, thanks to the Liberal Revolution of 1820. People were dealing with financial difficulties, and authorities, unfortunately, assumed that the aqueduct deaths were simply the result of desperate people committing suicide.

Soon enough, however, his luck ran out and the law caught up with him.

How Diogo met his end

How Diogo met his end

How His Head Ended Up in a Jar

With so many deaths at the aqueduct, people began to feel scared, and the aqueduct was closed down. It would not reopen again for many decades.

The closure of the aqueduct became a problem for Diogo.

He had to find a new place to commit his heinous crimes. His solution was to form a gang that would break into houses to rob and kill the residents.

In 1840, Diogo was captured and sentenced to death. Though the aqueduct murders remained unsolved, the jury had enough evidence to convict him of killing a family with his gang.

After Diogo's hanging, scientists and doctors of the Escola Medico Cirurgica of Lisbon decided they wanted to study the criminal's head. They wanted to understand what motivated a person to commit such evil deeds. Remember that Diogo was Portugal's first serial killer, and scientists thought they could learn important lessons from studying his remains.

What He Looks Like Now

In order to study Diogo’s head, scientists cut it off and preserved it. To this day, his head remains in a jar, floating in formaldehyde. Visitors who have seen it at the Faculty of Medicine at Lisbon University say that it looks like a potato with a face and hair.

Many have described his expression as calm. Some of my friends have noted that his serene expression is disconcerting. The jar seems to be a bit small for the head. We can see his lips pressing against the wall of the jar.

Arguably, the head of the serial killer is the most horrific exhibit at the university, and it is a fitting end to the cruel aqueduct murderer. He may be the only man in history to serve two different sentences: a death penalty and a life sentence in a jar full of embalming fluid.


1. Papathanasiou, Katerina (May 21, 2019). "Killer in a Jar: The Preserved Head of Diogo Alves". Valle Magazine.

2. Anna (May 16, 2019). "The Story of Diogo Alves. A Lisbon Serial Killer." Discover Walks Blog.

Questions & Answers

Question: Is the head in perfect condition as if when they chopped it off such as the same hair and etc?.

Answer: Like any body parts being preserved in embalming fluid, the head probably degraded a bit. The skin might have shriveled, the hair discolored and the eyes shrink a bit. But other than that, it is a near-perfect condition.