In May 2001, a marine survey team working off Cuba’s Guanahacabibes Peninsula detected unusual formations on the seafloor at a depth of roughly 2,000 feet. The team, led by engineer Paulina Zelitsky and her husband Paul Weinzweig, was under contract with the Cuban government to search for colonial-era shipwrecks. Using side-scan sonar, they located what appeared to be straight edges, circular outlines, and grid-like patterns spread across an area of about two square kilometers.
Zelitsky, who trained as an engineer in the former Soviet Union and later settled in Canada, described the sonar images as resembling a large urban center, though she cautioned that drawing conclusions that early would be irresponsible. The discovery drew quick attention from Reuters, the BBC, and National Geographic. The Center for Marine Archaeology and Anthropology at the Cuban Academy of Sciences also became involved, giving the find institutional credibility within Cuba.
The team returned to the site in July 2001 with a remotely operated vehicle equipped with cameras and lights. They brought along Manuel Iturralde, a senior geologist from Cuba’s Natural History Museum. The footage revealed massive blocks of stone, some measuring roughly eight by ten feet, sitting at depths between 600 and 750 meters. Some blocks appeared stacked on top of one another, while others stood in isolated clusters. Weinzweig described formations stretching as long as 400 meters and rising as high as 40 meters. He later compared the site to megalithic structures such as Stonehenge.
Equipment problems limited the survey to the outer edge of the formation, so its full scale was never confirmed. The site sat on a plateau that some team members believed formed the base of a mud volcano, positioned along what appeared to be an active geological fault line. Zelitsky also noted that the material in the footage looked like hewn granite, even though Cuba and the nearby Yucatan Peninsula are composed mostly of limestone. Iturralde called the formations peculiar and told reporters he could not fully explain them geologically.
The team’s credibility with the Cuban government added weight to the discovery. Over years of survey work, they had located around 20 shipwrecks, including the USS Maine, the battleship whose 1898 explosion in Havana Harbor helped trigger the Spanish-American War. That track record gave the smaller, stranger discovery institutional backing it might otherwise have lacked.
Iturralde raised a significant problem for any theory involving human construction. Global sea levels during the last ice age dropped by only about 100 meters at their lowest point. If the seafloor near Guanahacabibes had been dry land then, it would now sit under roughly 100 meters of water, not 700. Iturralde estimated that reaching this depth through normal geological processes could have taken around 50,000 years, far beyond the timeframe of any confirmed human civilization capable of large-scale stone construction. The earliest known such structures, such as the temples at Göbekli Tepe in modern-day Turkey, date back roughly 11,000 years.
Iturralde also noted that local folklore, including Maya and Yucateco stories, described an island home for ancestors that sank beneath the sea. Some have theorized a land bridge once connected Cuba to the Yucatan Peninsula, though no confirmed geological evidence supports that idea at a depth consistent with this site. The Yucatan Channel sits in a tectonically active zone where the Caribbean and North American plates shift along faults, a setting that could, in theory, produce sudden changes in seafloor elevation. No documented earthquake has been linked to the site’s depth.
Outside experts reviewed the images with varying degrees of skepticism. National Geographic senior editor John Echave called the formations interesting anomalies but said the site would remain difficult to characterize without physical examination. Robert Ballard, the oceanographer who located the Titanic, expressed doubt that the structures were human-made, noting that researchers often see what they hope to find in low-resolution sonar data. Iturralde remained in the middle, telling the Washington Post the formations were strange and unlike anything he had seen before, without a ready explanation.
Media coverage quickly attached the label of a Caribbean Atlantis to the site, drawing on Plato’s account of a sunken island nation. Zelitsky and Weinzweig never used that term themselves. Zelitsky later rejected the comparison, saying that if the formations were built by people, they more likely represented remains of a regional culture rather than a lost civilization from Greek legend.
The site is one of several underwater formations that have sparked similar debates. The Yonaguni Monument off Japan, discovered in 1986, consists of terraced rock with sharp edges that some researchers argue shows signs of human modification. Geologist Robert Schoch has argued the formation can be explained through natural sandstone fracturing. The debate there remains unresolved. The Bimini Road off the Bahamas attracted Atlantis speculation in the 1960s, but geological study determined the blocks were naturally occurring beach rock. By contrast, the confirmed prehistoric settlement of Atlit Yam off Israel, dating back nearly 9,000 years, sits in shallow water consistent with known sea level history and has produced artifacts, organic material, and human remains. The Cuban site has yielded none of that evidence.
Side-scan sonar builds images from sound waves rather than light, and the same formation can look different depending on the angle of the sonar pass. This indirectness leaves room for pareidolia, the tendency to find familiar patterns in ambiguous visual data. Ballard raised this concern when reviewing the Cuban images. Without physical samples brought back to a laboratory, sonar data alone cannot settle the question.
A planned follow-up expedition was canceled due to funding problems, according to oceanographer Sylvia Earle, who had been involved in confirming the mission. Political complications also played a role. The long-standing trade embargo between Cuba and the United States limited scientific cooperation and equipment sharing, since many capable deep-sea vehicles are owned by American institutions. Zelitsky and Weinzweig’s contract focused on treasure hunting rather than archaeology, and hundreds of Spanish colonial shipwrecks scattered nearby continued to demand their attention. The formations near Guanahacabibes remained a side project.
More than two decades later, no major institution has organized a return trip. Modern autonomous vehicles and high-resolution multibeam sonar could produce maps detailed enough to distinguish individual rock faces, and a physical sample could answer the granite versus limestone question through laboratory testing. None of that has been applied to this stretch of seafloor.
The story has resurfaced repeatedly online in recent years, with new audiences rediscovering the original 2001 images. Some recent coverage has described the site as a lost city potentially older than the Egyptian pyramids, language bolder than anything the original researchers used. One figure circulating online estimates the formations are roughly 6,000 years old, but no dated sample has ever been recovered, and no scientific paper backs the estimate. No new dives have been conducted, no new sonar surveys have been run, and no sample has been brought up for testing.
The most likely explanation remains natural rock, possibly limestone platforms fractured by tectonic activity, coral terraces that grew into unusually regular shapes, or disturbed stone surrounding a mud volcano. All three processes are well documented elsewhere and can produce blocky, organized shapes. Less than a quarter of the world’s ocean floor has been mapped in detail, and this stretch of Caribbean seafloor has barely been touched since the summer of 2001.
Until a return expedition is funded, the site remains an unanswered question under roughly 700 meters of water. Nobody has gone back down, and that lack of resolution, rather than any new discovery, is what has kept the story alive.
