28 August 2025 The Future is the Product of the Past

Traces of Pozzolan Dust from Phlegraean Fields Found in a 1st-Century Roman Hydraulic Structure Submerged in Venetian Lagoon

In the San Felice Canal, in the northern Venetian Lagoon, a material used as an additive in Roman concrete was discovered: pulvis puteolana, a volcanic ash from the Phlegraean Fields near Naples.

Researchers from the University of Padua, the Ca’ Foscari University of Venice, and the University of Modena and Reggio Emilia collaborated to document this discovery, which was published in the scientific journal PLoS ONE.

Researchers from the University of Padua detected the utterly unexpected presence of volcanic pumice from the Phlegraean Fields in Naples by analyzing samples of the mortars used to coat and bind the Roman well-cistern (1st c. CE), which is currently submerged more than three meters deep in the northern portion of the Venetian lagoon.

This material is described in detail by architects and treatise writers Vitruvius and Pliny the Elder as a powder (pulvis) with extraordinary properties, enabling ancient mortars and concretes to solidify in anaerobic environments and even underwater. Extracted from the area around ancient Pozzuoli (Puteoli), Latin authors recommended its use in the construction of port infrastructures made of concrete poured directly into the sea. 1,800 years before the discovery of Portland cement, pulvis puteolana gave ancient concretes exceptional resistance to structural loads, weathering, and the aggressive submerged environment, ensuring extraordinary durability that has recently revived the “myth” of Roman concrete.

The remains of the submerged "Venetian well," documented thanks to underwater 3D surveys, and the mortar samples collected. Image Credit: University of Padua
The remains of the submerged “Venetian well,” documented thanks to underwater 3D surveys, and the mortar samples collected. Image Credit: University of Padua

The research sheds light on advanced Roman construction techniques and the commercial dynamics of the Mediterranean.

The subject of study is a 1st-century CE Roman hydraulic structure, considered a precursor to the “Venetian wells,” designed to capture and store fresh water.

The Venetian-style well is a hydraulic structure used since Roman times in the Upper Adriatic territories for the collection and storage of fresh water, which we have been able to document and study underwater, thanks also to innovative photogrammetric technologies, add Carlo Beltrame and Elisa Costa, a professor and a researcher from the Department of Humanities at the Ca’ Foscari University of Venice and authors of the underwater studies conducted under a permit from the Ministry of Culture, with the oversight of the Soprintendenza Archeologia Belle Arti e Paesaggio of the Municipality of Venice and the Lagoon.

Advanced laboratory technologies have made it possible to perform sophisticated microscopic and geochemical analyses on rocks and minerals, even when they have been finely ground into a micrometric-sized powder. These analyses were never performed on archaeological materials until a few years ago, but they have made it possible to determine the origin of the pulvis.

“The fingerprint of the volcanic pulvis,” emphasizes Tommaso Giovanardi, a professor in the Department of Chemical and Geological Sciences at the University of Modena and Reggio Emilia, “was traced thanks to ultra-high-resolution instruments, such as Laser Ablation Inductively Coupled Plasma Mass Spectrometry, which allow us to obtain extremely detailed geochemical data even on very tiny fragments of geological material.”

Highlighted are the clasts of pulvis puteolana included in the mortar samples and analyzed with geochemical investigations. Image Credit: University of Padua
Highlighted are the clasts of pulvis puteolana included in the mortar samples and analyzed with geochemical investigations. Image Credit: University of Padua

The profile of these small inclusions was then compared with a vast reference database created by researchers from the Departments of Cultural Heritage and Geosciences at the University of Padua, which gathers the compositional profiles of over 1,000 geological samples of compatible volcanic products. Through the comparison of chemical tracers, the compatibility with the volcanic dust from Campania was unequivocally certified.

Lastly, the study highlights the remarkable originality with which the Venetian ancestors adapted the prominent Vitruvian architectural forms to the unique architectural and environmental requirements of the Lagoon in its delicate balance between water and land, while also highlighting the close ties between Northern Italy and the most advanced Roman engineering knowledge.

University of Padua

https://doi.org/10.1371/journal.pone.0313917

Cover Image: Wikipedia Commons

Related Articles

Statue Head of Goddess Tyche Discovered in Bulgaria

8 December 2024

8 December 2024

A remarkably crafted head of a large statue of the Greek goddess Tyche was recently unearthed during the excavations of...

Czech archaeologists discovered a unique bronze belt buckle dating back to the eighth century

12 December 2023

12 December 2023

Czech archaeologists have unearthed a bronze belt buckle from the early Middle Ages, depicting a snake devouring a frog-like creature....

Metal signature of Roman 19th Legion identified at Teutoburg battle site that shook Rome in AD9

5 December 2022

5 December 2022

Researchers in Germany have identified the metallurgic signature of the Roman 19th Legion in artifacts recovered from the Battle of...

6000-Year-Old Salt Production House Rewrites Europe’s History

31 March 2021

31 March 2021

Archaeologists in the UK have found an ancient stone age-era salt-production house in North Yorkshire, estimated to be older even...

Hidden Roman Passage Unearthed Beneath Split: A Secret Gateway into Diocletian’s Palace Revealed

23 June 2025

23 June 2025

A groundbreaking discovery beneath Hrvojeva Street, near Diocletian’s Palace, is reshaping our understanding of Roman life and architecture in the...

Incredible Mayan Inventions and Achievements

31 July 2022

31 July 2022

The Mayans excelled at agriculture, pottery, writing, calendars, and arithmetic, leaving an incredible quantity of spectacular architecture and symbolic artwork...

New Discoveries at Ancient Greek City of Paestum’s ‘Little Doric Temple’ in Italy

16 April 2023

16 April 2023

Archaeologists have made a series of extraordinary discoveries that may fundamentally alter the understanding of the past of the ancient...

Archaeologists Find 11 Sealed Middle Kingdom Burials Full of Jewelry in Luxor, Egypt

4 November 2024

4 November 2024

The South Asasif Conservation Project, an Egyptian-American mission working under the auspices of the Ministry of Tourism and Antiquities, has...

New study says earliest recorded kiss occurred 4500 years ago in Mesopotamia

18 May 2023

18 May 2023

The University of Copenhagen according to researchers, humanity’s earliest recorded kiss occurred around 4,500 years ago in the ancient Middle...

An exciting discovery in Hattusa, the capital of the Hittites

11 September 2022

11 September 2022

It is aimed to reach new information about the traditions of the Hittite civilization with 249 new hieroglyphs discovered in...

World’s oldest wooden structure ‘476,000 years old’ discovered in Zambia

20 September 2023

20 September 2023

An ancient wooden structure found at Kalambo Falls, Zambia—dated to about 476,000 years ago—may represent the earliest use of wood...

Recent excavations at Girsu uncovered innovative civilization-saving technology of Ancient Sumerians

19 November 2023

19 November 2023

In ancient city Girsu, located near the modern city of Nasiriyah in southern Iraq, revealed through a recent excavation by...

A Large Copper Age Necropolis Discovered in Italian Town

16 February 2024

16 February 2024

In the town of San Giorgio Bigarello, near the northern Italia city of Mantua, a large Copper Age necropolis dating...

Was the mystery of Noceto Vasca Votiva the water ritual?

13 June 2021

13 June 2021

The Noceto Vasca Votiva is a one-of-a-kind wood building discovered in 2005 on a tiny hill in northern Italy. The...

Battle of the Egadi Islands: Rome’s deadly weapons discovered off Sicily

3 September 2021

3 September 2021

Underwater archaeologists from the Soprintendenza del Mare Regione Siciliana, RPM Nautical Foundation, and the Society for the Documentation of Submerged...