Clarkson University Professor Collaborates with Archaeologists in Spain to Investigate Galician Roman Saltworks

• Home >
• News & Events >

Clarkson University Professor Allen Gontz recently joined Spanish archaeologists in Galicia, Spain, to investigate nearly 2,000-year-old Roman salt production sites using advanced, non-invasive geophysical technology.

Gontz, a professor of applied geology in Clarkson's Department of Civil and Environmental Engineering, collaborated with Brais X. Currás of the Institute of History at the Spanish National Research Council (CSIC) to study ancient coastal saltworks along the northwestern coast of the Iberian Peninsula.

Salt was one of the most valuable resources in the Roman Empire, used for food preservation, medicine, leather processing and trade. Roman soldiers were sometimes paid in salt, giving rise to the word "salary." Despite its importance, relatively few Roman salt production sites have survived.

Galicia contains the largest known concentration of Roman marine saltworks. Archaeological evidence shows many of these industrial-scale facilities were built between 70 and 50 B.C. and operated through the third century A.D. Researchers believe additional sites remain buried beneath the landscape and have yet to be discovered.

During fieldwork in June, Gontz and the CSIC research team used ground-penetrating radar (GPR) and high-precision GPS technology to survey Roman saltworks near Oia, south of Vigo. The equipment allows researchers to map structures hidden beneath the ground without excavation.

"Our goal is to better understand how people used the landscape and its resources, and what social or environmental factors may have contributed to the decline of these large-scale salt production centers," Currás said.

Currás is a leading expert on ancient salt production in the Iberian Peninsula and studies both Roman saltworks and earlier fortified settlements known as castros.

The project combines archaeological research with geological analysis. Gontz's expertise in geophysics and historic shoreline reconstruction will help researchers identify buried saltworks and better understand how coastlines have changed over time.

Galicia's coastline is particularly important because geological uplift has gradually raised portions of the land. As a result, some ancient saltworks that once operated at sea level are now exposed on land. At the same time, rising sea levels and coastal development pose growing threats to archaeological sites throughout the region.

"With climate change and rising sea levels, coastal cultural heritage sites are under constant threat," Gontz said. "The clues these saltworks provide about past sea levels, environmental conditions and human activity are often hidden beneath our feet."

By analyzing subsurface soil layers, researchers hope to reconstruct the landscape as it existed when Romans harvested salt nearly two millennia ago. The findings may provide new insights into ancient industries, environmental change and the relationship between human societies and coastal ecosystems.

The collaboration also strengthens international research partnerships between Clarkson University and Spanish institutions while creating new opportunities to study how past civilizations adapted to changing environments.

Gontz earned his doctorate and masters in Earth and geological sciences from the University of Maine and bachelor's degrees in biology and applied geology from Lock Haven University. His research has examined how large-scale landscape changes affect societies in locations including Australia, New Zealand, Peru and the United States.

Additional information

The roman saltworks of the Atlantic coast of Gallaecia: Traces and evidence of a large sea salt production complex - ScienceDirect