The University of Lisbon’s Faculty of Medicine is the proud owner of a severed, yellowish head submerged in a formaldehyde solution in a big glass jar. The head belonged to a man called Diogo Alves. But what did he do to deserve losing his head? And why did someone preserve it?

Diogo Alves is said to be Portugal’s first serial killer. He was born in 1810 in Galicia, Spain, in a peasant family, but moved to Lisbon at the age of 19, following his parent’s orders to find work in the city. He worked a few different jobs, but as a poor young man from out of town there is only so much to choose from and so he became a servant for wealthy people. Sticking to jobs was apparently not one of Diogos strong points and eventually he began to fall into a life of crime. He drank and he gambled, stopped writing his parents letters and eventually found himself with a woman, Maria Gertrudes, who is believed to be the reason he started murdering people in 1836, as she put pressure on him to provide for her.

Diogo stole and falsified keys, which is how he gained access to the Aquedato das Aguas Livres, an aqueduct that still stands in Lisbon today. It was built under the orders of King John V, back in 1731 to help with the lack of drinking water in the city, though the first bit of water only started flowing in 1748. It was considered one of the most remarkable examples of Portuguese engineering and it even managed to remain intact when the 1755 earthquake hit the city. At its highest point, it measured 65 metres from the ground.

Once Diogo had access to this impressive construction, he would hide there, wait for clueless victims to pass by, rob them, blindfold them and then march them up to the top of the aqueduct, where he would throw them off. The 65 metre drop meant certain death and gave Diogo an opportunity to hide his murders behind what could look like suicide.

Between 1836 and 1839 he murdered an estimated 70 people like that. This is how he earned his second nickname “The Aqueduct Murderer” though I think “The Aqueduct Assassin” has a better ring to it. It is his second nickname, because back when he was a young boy, Alves fell off a horse and hit his head, which led to everyone callinghim “Pancada” which translated to “blow”. Turns out kids that lived around 1820 are just as mean as kids today.

You might wonder now how 70 people dying in the same spot, within three years, didn’t raise suspicion. Well, it did eventually, but Diogo took advantage of the financial and economic crisis resulting from the liberal revolution in 1820, and a crisis like this could explain arise in suicides.

Soon though, and because of all the deaths, people were freaked out, so the city closed the aqueduct and it would not be opened again for many years to come. Diogo had lost the one spot in the city where he could rob and kill people without being caught. But he was determined to continue the path he was on and so he brought together a group of criminals who would break into wealthy residencies, some of whom he worked for in younger years, to rob the place and murder any witnesses.

Finally, in 1840, Diogo Alves was captured and sentenced to death. They could never prove the aqueduct murders but he and his gang were caught for murdering four family members and robbing their house.

He was the penultimate criminal to be hanged in Portugal and his actions and cold bloodedness intrigued scientists at the time. They decided to cut off his head and keep it, to then later study his brain and find out what led Portugal’s first serial killer to commit so many horrifying crimes. Through my research I could not find any evidence of anyone actually studying his brain and releasing results. To this day it is preserved in near perfect condition in the University of Lisbon’s Faculty of Medicine.

So while the severed head of a vicious psychopath might not exactly be considered a gem, it is quite an interesting hidden story, since the part of the university that is home to the remains of Diogo Alves is not usually accessible by the public.