Underwater archaeology involves exploring and preserving archaeological treasures submerged in oceans, lakes, and rivers. The emergence of scuba diving in the mid-20th century helped propel the development of underwater archaeology. The submerged sites studied by underwater archaeologists consist of shipwrecks, ancient human remains, and sunken settlements (Blakemore 2021). Some practical challenges and difficulties of underwater archaeology include access to sites, transportation of equipment, weather conditions, specifically the tides and the dynamic nature of water, data interpretation, international and local laws, and the need for skilled divers. LiDAR, sonar, advanced imaging aids, remote sensing devices, advanced photography, and submersibles all aid archaeologists in discovering and documenting submerged sites and artifacts (Blakemore 2021). Forming strong relationships with local communities can be very important for underwater archaeologists because the locals may have valuable knowledge of the waters being explored. For example, local fishers played a crucial role in assisting archaeologists in the discovery of 23 shipwrecks near Fourni, Greece (Blakemore 2021). 

Figure 1. Example of a LiDAR map of Inlet, Virginia.

Learn more about the LiDAR technology: https://oceanservice.noaa.gov/facts/lidar.html#:~:text=Lidar%2C%20which%20stands%20for%20Light,variable%20distances 

One interesting example of an underwater discovery is the identification of submerged DNA in Chios, Greece by archaeologist Brendan Foley and environmental geneticist Maria Hansson. Foley had surveyed a classical shipwreck near the Greek island of Chios but couldn’t identify the cargo. Hansson suggested DNA analysis on the recovered amphorae (Archaeological Institute of America 2009). Amphora is a type of ancient vessel or container, typically made of clay or ceramic, with a distinctive shape. Hansson found genetic traces of olive, oregano, and tree resin, providing direct evidence of the ship’s cargo. Foley and Hansson’s findings provided evidence about the ancient economy. They also demonstrated that, in certain instances, the marine environment can be conducive to DNA preservation (Archaeological Institute of America 2009). This discovery informs fellow archaeologists that conducting DNA analyses in aquatic environments is indeed feasible and can prove a lot about the ancient economy.

Another interesting example of an underwater discovery was in 2013 when a chemical analysis was conducted on an intact, 2,000-year-old Roman medicinal pill discovered in the Relitto del Pozzino, a 2,000-year-old sunken ship off the coast of Tuscany. The shipwreck was located near the Etruscan city of Populonia, a significant Mediterranean Sea trade hub (Mosquera 2019). The excavation, carried out in the 1980s and 90s, uncovered various items, including lamps, glass bowls, bronze jugs, and a medicine chest containing surgical tools, 136 wooden drug vials, and tin vessels with medicinal tablets (Mosquera 2019). These tin vessels remained sealed, preserving the pills. The 2013 chemical analysis revealed that the tablets contained zinc compounds, iron oxide, starch, beeswax, pine resin, and plant-derived materials, suggesting they were used as eye medicine (Mosquera 2019). This discovery and chemical analysis provided valuable evidence and insight into medicinal history.  

Figure 2. Image of tin vessel containing medicinal pills in the Relitto del Pozzino. Photograph by Enrico Ciabatti.

In southern Greece, the site of Pavlopetri, previously explored in the late 1960s, gained renewed archaeological significance in 2009 due to advanced technological methods (Smith 2009). Dating back 5,000 years, Pavlopetri is recognized as the oldest known submerged city. While older underwater settlements exist, Pavlopetri stands out due to its distinct urban characteristics (Smith 2009).

Figure 3. Image of the ruins of the ancient Greek city of Pavlopetri. Photograph by Nikos Pavlakis/Alamy Stock Photo.

Learn more about Palopetri: https://www.theguardian.com/science/2009/oct/16/lost-greek-city-atlantis-myth

The field of underwater archaeology offers new insights and discoveries concerning ancient civilizations, including their economic activities and medical practices. It plays a crucial role in comparing and tracing the evolution of human societies over time.

References: 

Archaeological Institute of America. “Diving into History – The Latest Underwater Discoveries .” Diving into history – the latest underwater discoveries – Archaeology Magazine Archive, 2009. https://archive.archaeology.org/0907/underwater/.

Blakemore, Erin. “Underwater Archaeology Facts and Information.” Culture, May 3, 2021. https://www.nationalgeographic.com/culture/article/underwater-archaeology.

Mosquera, Miguel. “The Five: Underwater Discoveries.” The Guardian, April 7, 2019. https://www.theguardian.com/technology/2019/apr/07/the-five-underwater-discoveries-archaeology-ancient-civilisations-lost-worlds.

Smith, Helena. “Lost Greek City That May Have Inspired Atlantis Myth Gives up Secrets.” The Guardian, October 16, 2009. https://www.theguardian.com/science/2009/oct/16/lost-greek-city-atlantis-myth.

US Department of Commerce, National Oceanic and Atmospheric Administration. “What Is Lidar.” NOAA’s National Ocean Service, October 1, 2012. https://oceanservice.noaa.gov/facts/lidar.html#:~:text=Lidar%2C%20which%20stands%20for%20Light,variable%20distances.