Posted on June 15, 2026
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A clamshell dredge rose from the Savannah River with more than mud in its jaws. Caught in the scoop was a rust-covered cannon, one of the heavy iron weapons that had rested underwater since the Revolutionary War. The find came during work to deepen a 40-mile section of the river, part of a $973 million harbor expansion project that led to a rare archaeological recovery.
Crews soon found more. By 2022, workers had recovered 19 cannons from the riverbed, each weighing more than 1,000 pounds. What first looked like a construction surprise became a story about British occupation, wartime river defenses, and Savannah’s place in the American Revolution.
The artifacts were found near Old Fort Jackson, where layers of mud and poor underwater visibility had hidden them for centuries. Officials first considered whether the weapons might be connected to Civil War wreckage nearby. Further study showed they were older, dating to the mid-1700s and the struggle for control of Savannah during the Revolutionary War.
Dredging Work Exposed Buried Artifacts
The first three cannons were found in late February 2021 as a hinged clamshell dredge prepared part of the river for deepening. The Associated Press reported at the time that workers also recovered a ship’s anchor and a large tool-shaped piece of wood that appeared to be a beam or plank. The size and condition of the objects made clear that the dredging project had reached a historically important part of the riverbed.
Work was temporarily halted in that area while officials decided whether more artifacts might be nearby. Divers surveyed the site, but the river’s poor visibility made direct inspection difficult. Experts then used sonar and other remote sensing tools to search the sediment, a method that helped locate additional 19 cannons without relying only on what divers could see underwater.
In March 2022, the U.S. Army Corps of Engineers, Savannah District, said maintenance dredging had recovered enough additional cannon to bring the total to 19. The Corps said some of the weapons had not been identified earlier because of the way they were positioned in the river sediment. Their buried placement helped explain why the objects had remained unseen during earlier work in the area.
Evidence Points To A British Wartime Obstruction
Analysis confirmed that the cannons were manufactured in the mid-1700s, according to the Corps. A final conclusion about their exact origin was still pending, but archival research pointed to the HMS Savannah as the source of all or most of the artifacts. The ship was one of the vessels connected to British efforts to block access to Savannah during the war.
The Corps said the HMS Savannah, HMS Venus and other troop transports were sunk with their armaments intact in an area called Five Fathom Hole. Those sunken vessels created obstructions meant to block Savannah from the advance of the French fleet in September 1779. That happened shortly before the Siege of Savannah in October 1779, when American and French forces tried to retake the city from the British.
That history gives the cannons their larger meaning. They are not only loose weapons from the Revolutionary War period. They appear to be physical evidence of a defensive measure used by British forces as they tried to hold Savannah, a port city whose river access mattered during the conflict.
Some of the recovered cannons were still loaded, suggesting they may have been aboard a vessel that sank quickly. Historians first considered whether the weapons came from HMS Rose, a British ship scuttled in 1779. They later determined that the Rose had gone down farther upstream and that the artillery had not been aboard it.
Restoration Took Years After The Recovery
After the cannons were removed from the river, two remained covered in rust and sediment and went on display at the Savannah History Museum in 2021. The other 17 were sent to a conservation lab at Texas A&M University after specialists determined that the loaded weapons did not pose a safety hazard. That step was necessary before conservators could begin the careful work of stabilizing the objects.
Iron artifacts that spend centuries underwater can be fragile once they are exposed to air. Conservators worked for several years to treat and restore the 17 cannons, turning objects pulled from the riverbed into artifacts stable enough for public display. The sources do not describe every conservation step, but they make clear that the work was specialized and took years.
