Marine archaeologists have announced a major breakthrough in the dating of submerged stone structures found off the coast of Saurashtra, India. Published on April 1, 2026, the study used Thorium-230/Uranium dating of calcium carbonate crusts found on basalt blocks to establish that the foundations were laid approximately 15,000 years ago, during the Late Pleistocene.
The structures, which appear to be part of an ancient coastal protection or harbor system, suggest that pre-Holocene populations possessed advanced skills in stone masonry and maritime engineering. This dating significantly precedes the generally accepted timelines for urban construction in South Asia and indicates that organized civil engineering emerged in response to the first pulses of post-glacial sea-level rise.