Researchers dugout canoe with stone tools and traveled from Taiwan to Japan

A team of researchers has successfully recreated a 30,000-year-old voyage by paddling the "Sugime" dugout canoe 140 miles from Taiwan to Japan's Yonaguni Island in approximately 45 hours, using only Paleolithic stone tools for construction and natural navigation methods to demonstrate how early humans might have intentionally crossed the powerful Kuroshio Current, one of the world's strongest ocean currents.

Sugime Dugout Canoe Construction

The Sugime dugout canoe, constructed in 2019, was meticulously crafted using techniques that mirrored those available to Paleolithic seafarers. The team felled a one-meter-thick Japanese cedar tree using replicas of 30,000-year-old stone tools found at Japanese Paleolithic sites. After removing the bark, they carved a seating area in the center of the 7.5-meter (24-foot) trunk and, inspired by burn marks found on Jōmon period dugouts (dating from around 14,000 BCE), polished the inside with fire—a technique that would have been available to ancient craftspeople.explorersweb+2

Unlike modern dugout canoe construction that often employs chainsaws, axes, and adzes, the research team relied solely on primitive methods to create an authentic vessel. This painstaking process began in 2017 and resulted in a seaworthy craft capable of carrying five paddlers. The completed canoe demonstrated that Upper Paleolithic tools found in the Japanese Archipelago were indeed sufficient for constructing vessels capable of crossing dangerous ocean currents, providing compelling evidence for how early humans might have reached remote islands like those in the Ryukyu chain.popsci+3

Kuroshio Current Navigation Challenges

The Kuroshio Current presented a formidable obstacle for ancient seafarers attempting the Taiwan-Yonaguni crossing. Known as the "Black Current" for its dark, cobalt blue waters, it ranks among the world's three largest ocean currents and flows at approximately 25-65 million cubic meters per second. This powerful oceanic river rivals the Gulf Stream in strength and creates significant navigational challenges that required sophisticated understanding from Paleolithic voyagers.wikipedia+2

Successfully traversing the Kuroshio demanded specific strategies that researchers have now identified through simulations and experimental voyages. Key factors included selecting suitable departure points, implementing effective paddling techniques to counteract the current's force, and utilizing high-level navigation skills. Modern vessels crossing the Pacific can achieve up to 18% fuel savings by properly accounting for the Kuroshio's flow patterns, highlighting how critical current awareness remains even with today's technology. For Paleolithic travelers, recognizing and adapting to this powerful current wasn't just about efficiency—it was essential for survival.napa+1

Taiwan-Yonaguni 45-Hour Voyage

The historic voyage from Taiwan to Yonaguni Island began on July 7, 2019, when the five-person crew (one Taiwanese and four Japanese, including one woman) departed from Cape Wushibi in Taitung County, Taiwan at 1:40 p.m. After being delayed twice due to unfavorable weather conditions, the team finally embarked on their journey across the 205-kilometer stretch, relying solely on natural navigation methods—using only the stars, sun, and wind for bearings. The expedition, a collaboration between Japan's National Museum of Nature and Science and Taiwan's National Museum of Prehistory, successfully reached Yonaguni Island at 11 a.m. on July 9, completing the crossing in approximately 45 hours.explorersweb+3

The successful voyage came after two previous failed attempts using different vessel designs. In 2017, the team's bamboo raft "Ira I" couldn't overcome the powerful Kuroshio Current, while the 2018 attempt with the improved "Ira II" proved vulnerable to ocean waves and water damage. The Sugime dugout canoe succeeded where these earlier vessels failed, demonstrating that Paleolithic humans could have intentionally navigated to Japan rather than arriving by accident. As expedition leader Yosuke Kaifu noted, "You can see Yonaguni from some of the high peaks in Taiwan, but you don't arrive by chance (at Yonaguni) just by drifting." The entire journey was meticulously documented using 360-degree cameras, support vessel photography, and drone footage, providing comprehensive evidence of this remarkable achievement in experimental archaeology.nippon+2