30 June 2025 The Future is the Product of the Past

Ground-penetrating radars reveal hidden passages, described in Leonardo’s drawings

As part of a PhD thesis, an innovative technological investigation conducted by the Politecnico di Milano, in collaboration with the Sforza Castle and with the technical support of Codevintec, revealed numerous hidden passages under the Sforza Castle. These structures hint at secret passageways depicted in the drawings of renowned artist and engineer Leonardo da Vinci.

As a symbol of Italian history, the castle has long captivated the attention of historians, engineers, and architects. Since its construction in the 15th century, it has functioned as a fortress, residence, and seat of power in Milan.

According to researchers from the Politecnico di Milano (Polytechnic University of Milan), some of the tunnels were probably used by the military, while another that was formerly connected to a nearby church was used by a grieving duke to sneak into his wife’s grave.

Numerous legends have been created over the years regarding its underground chambers. In one of these stories, Ludovico il Moro, Duke of Milan, is said to have visited his wife, Beatrice d’Este, through a secret passageway. Renowned polymath Leonardo da Vinci’s drawings also featured the underground passage.

The duke is said to have never fully recovered from the loss—entering, in the words of the historian Luciano Chiappini, “an almost maddening mourning” (involving the deification of his wife, around which he created something of a cult) that is suspected to have contributed to his downfall a few years later.

Geophysical surveys are undertaken at Milan's Sforza Castle. The buried passageways were found within the castle's outer wall. Credit:  Politecnico di Milano
Geophysical surveys are undertaken at Milan’s Sforza Castle. The buried passageways were found within the castle’s outer wall. Credit: Politecnico di Milano

This passage, immortalized in Leonardo’s drawings, now, thanks to technology, it seems that its existence can be confirmed. But there are numerous secret walkways.

Now, a study applying advanced ground-penetrating radar technology provides fresh evidence that such underground corridors and similar architectural features may indeed exist beneath the castle.

The investigation used advanced technologies, including ground penetrating radars and laser scanners, to accurately map and document the Castle’s subsurface and its underground structures. These instruments made it possible to reveal cavities and underground walkways at a depth of a few decimeters.

“The aim is to create a digital twin of the Sforza Castle,” said Franco Guzzetti, a geomatics professor at the university, in a statement.

This, he added, will be a model “that not only shows the current appearance of the castle, but also allows us to explore the past by revealing ancient structures that are no longer visible.”

The information gathered has not only provided historical documentation but also created new prospects for the Castle’s tourism development. Visitors would be able to explore underground spaces and inaccessible historical locations through the use of augmented reality technologies and the development of virtual pathways, providing an immersive experience that blends innovation and history.

 Politecnico di Milano

Cover Image Credit: Wikipedia Commons CC BY-SA 4.0

Related Articles

Oldest Fortresses in the World Discovered in Siberia

8 December 2023

8 December 2023

Archaeologists from Freie Universität Berlin together with an international team have uncovered fortified prehistoric settlements in a remote region of...

Roman-era Pottery Workshop discovered in Alexandria

29 April 2022

29 April 2022

The Egyptian archaeological mission discovered a Roman-era pottery workshop at the site of Tibet Mutawah, west of Alexandria. The researchers...

Unique ‘Excalibur’ Sword Found Upright in Ground Unearthed in Spain Holds Islamic Origins

26 April 2024

26 April 2024

Researchers have finally unraveled the mysteries of the historical sword discovered in Spain 30 years ago, which they named ‘Excalibur’...

Pendants and beads reveal nine European Cultures living across the continent 30,000 years ago

1 February 2024

1 February 2024

In a new study, researchers have constructed a continent-wide database of personal ornaments worn by Europeans 34,000-24,000 years ago, a...

Neo-Assyrian underground complex discovered under a house in southeastern Turkey

11 May 2022

11 May 2022

An underground Iron Age complex has been found in Turkey that may have been used by a fertility cult during...

The greatest Anglo-Saxon treasure trove ever unearthed has been discovered by a metal detectorist

10 November 2021

10 November 2021

A metal detector in West Norfolk, England, unearthed 131 coins and 4 golden artifacts going back 1,400 years. This is...

Prehistoric Cave Art Handprints With Missing Fingertips Point to Ritual Amputation

3 January 2024

3 January 2024

Researchers who examined prehistoric cave art in France and Spain, a new interpretation of Paleolithic cave art proposes that prehistoric...

Mystery of the ‘Deserted Castle’ Unraveled: Austria’s First Roman Bridgehead Fort Discovered

18 April 2025

18 April 2025

Researchers have identified the first confirmed Roman bridgehead fort in Austria, located near Stopfenreuth on the Lower Austrian Danube floodplains....

First Major Iron Age Cemetery Discovered in the UAE: A 3,000-Year-Old Burial Site in Al Ain Region

22 April 2025

22 April 2025

A groundbreaking archaeological discovery has emerged from the Al Ain Region of the United Arab Emirates, revealing a 3,000-year-old necropolis...

New Archaeological Discoveries may Confirm What is Written in the Bible

22 March 2021

22 March 2021

The importance of what is written in the scriptures in the development of archeology is really great. It is possible...

Fossil of a hominid child who died almost 250,000 years ago discovered in South Africa

8 November 2021

8 November 2021

A team of international and South African researchers uncovered the fossil remains of an early hominid kid who died almost...

A female executive’s seal from 3000 years ago was discovered in Turkey

29 October 2021

29 October 2021

During the excavations carried out in southeastern Turkey’s Gaziantep’s Karkamış (Carchemish) Ancient City, seals and prints determined to belong to...

700 Years After Dante’s Death, His Handwritten Notes Are Discovered

11 July 2021

11 July 2021

Dante Alighieri, an Italian poet, and scholar are best known for his masterwork La Commedia (also known as The Divine...

Multiple Burials found at Çatalhöyük

17 September 2021

17 September 2021

Multiple burials were unearthed during the ongoing excavations in the house on the eastern mound of the Neolithic settlement Çatalhöyük....

134 ancient settlements discovered north of Hadrian’s Wall

26 May 2022

26 May 2022

134 ancient settlements have been found during a survey of the region north of Hadrian’s Wall in the United Kingdom....