Using high-resolution drone-based lidar, researchers uncovered the layout of a sprawling medieval city hidden within the mountains of southeastern Uzbekistan.
The findings challenge long-held assumptions about where major Silk Road settlements could exist and demonstrate how modern remote sensing continues to transform archaeological research.
Drone Lidar Maps a Hidden Medieval City
For decades, archaeologists believed that the largest urban centers along the Silk Road developed primarily in fertile lowland regions where agriculture could sustain large populations. Tugunbulak tells a different story.
Located approximately 2,000 meters above sea level in Uzbekistan’s Turkestan Range, the settlement remained largely invisible from ground level because centuries of erosion, vegetation, and terrain had obscured its architectural features. Traditional field surveys could identify scattered artifacts and isolated structures, but determining the city’s overall footprint proved nearly impossible.
Researchers from Washington University in St. Louis and Uzbekistan’s National Center of Archaeology deployed drone-mounted lidar to systematically survey the site. Digital terrain models removed vegetation and highlighted subtle topographic variations that corresponded to walls, streets, fortifications, terraces, and building foundations.
Revealing Tugunbulak’s True Scale
The lidar survey demonstrated that Tugunbulak was far larger than previously understood.
The mapped settlement covers roughly 120 hectares (about 300 acres), making it one of the largest known high-altitude medieval cities in Central Asia. The data revealed extensive defensive walls, multiple fortified complexes, road networks, plazas, and residential districts distributed across the mountainous terrain.
Rather than functioning as an isolated mountain outpost, Tugunbulak appears to have been a substantial urban center occupied between the sixth and tenth centuries. Archaeological evidence suggests the city was closely connected to regional trade routes and possessed the infrastructure necessary to support a significant permanent population.
Researchers also documented the nearby settlement of Tashbulak, located only a few kilometers away. Together, the two sites indicate that mountain communities played a much larger role in Silk Road commerce than historians previously recognized.
Changing the Story of the Silk Road
The discovery extends beyond simply locating another lost city.
Excavations have uncovered evidence that Tugunbulak served as an important center for iron and steel production. Preliminary investigations identified furnaces, kilns, industrial facilities, and slag deposits associated with metalworking, suggesting the city supported specialized manufacturing in addition to regional trade.
Its location challenges conventional models of medieval urban development. Historians traditionally associated large Silk Road cities with river valleys and agricultural production. Tugunbulak demonstrates that sophisticated urban communities could also thrive in rugged highland environments by leveraging mineral resources, metallurgy, and strategic trade connections.
Researchers believe the settlement’s economy likely combined industrial production with livestock, wool, and commerce moving through mountain trade corridors linking larger regional markets. The findings suggest high-altitude settlements were active economic centers rather than temporary caravan stops.
A New Role for Lidar in Archaeology
Beyond its historical significance, Tugunbulak demonstrates how lidar continues to reshape archaeological investigation.
Traditional mapping of a mountainous site covering hundreds of acres would require years of fieldwork. Drone-based lidar allowed researchers to rapidly produce high-resolution digital elevation models capable of revealing subtle archaeological features hidden beneath vegetation and surface erosion.
The survey also provided a permanent three-dimensional record that researchers can analyze repeatedly without disturbing the site. Combined with excavation data, GIS analysis, and computer modeling, these datasets allow archaeologists to reconstruct urban layouts, identify previously unknown structures, prioritize excavation targets, and better understand how ancient communities interacted with challenging landscapes.
As lidar systems become more accessible and drone platforms continue to improve, similar surveys are expected to uncover additional archaeological sites in regions where dense vegetation, rugged terrain, or centuries of natural processes have concealed evidence of past civilizations.
For the geospatial industry, the Tugunbulak project represents another example of lidar moving beyond traditional mapping applications. Whether documenting forests, infrastructure, disaster zones, or archaeological landscapes, high-resolution laser scanning continues to reveal information that would otherwise remain hidden, expanding the role of remote sensing in both scientific research and cultural heritage preservation.
Read More: Drone Lasers Uncover a Medieval “City of Iron” Hidden for 1,000 Years in Central Asia’s Mountains
