Archaeologists have identified an exceptionally large Bronze Age settlement on the vast Kazakh steppe that significantly changes the picture of Central Asian prehistory. The site is Semiyarka (Kaz. Semiyarka), translated as "City of Seven Ravines," for which recent research shows that more than three and a half millennia ago it functioned as a regional center for large-scale bronze production. Systematic geophysical prospecting, targeted excavations, and detailed material analysis have revealed a planned settlement of immense scale with clearly separated residential and industrial zones and a monumental structure at the very core of the settlement.
The latest review of results was provided by an international team of experts from University College London (UCL), Durham University, and Toraighyrov University, and key findings were published on November 18, 2025, in the journal Antiquity. Semiyarka occupies approximately 140 hectares on a rise above the Irtysh River in the present-day Abai Region in northeastern Kazakhstan. In the center of the settlement, there was a larger building of special purpose – public, communal, or ritual – while rows of rectangular earthen mounds marked the foundations of multi-room houses arranged in regular lines.
Why Semiyarka is the discovery of the decade
Semiyarka is exceptional in scale and degree of organization. In a region where mobile communities were long considered the rule, a permanent and planned settlement is revealed here. Its size far exceeds most contemporary sites, and the clear separation of residential and industrial zones suggests a higher level of labor coordination than previously assumed for steppe cultures of the Bronze Age. Scientists therefore propose that we view Semiyarka as an "urban hub" – a place that simultaneously retained characteristics of mobility and developed permanent infrastructure necessary for large-scale metallurgical production.
The location of the settlement reveals the logic of its development. Situated on a plateau above the Irtysh, with good communication towards the Altai ore zones of copper and tin, the site had access to key raw materials and river or steppe routes. Such a combination of resources and logistics explains how it was possible to maintain an operation that required a constant supply of ore, fuel, and labor, as well as supervision over technological processes.
How it all began: from first observations to systematic research
The site was spotted in the early 2000s by researchers from Toraighyrov University. Occasional mapping and checks followed, but only the recent international campaign enabled a complete "reading" of the space. Low-invasive methods were applied – aerial and drone imagery and geophysical techniques – to create precise maps of the layout of buildings, embankments, and possible streets. Then, test excavations were opened at key points, especially in the center of the settlement and in the zone suspected to be industrial. Such an approach simultaneously protected the integrity of the site and ensured representative samples for laboratory analyses.
The first few seasons resulted in the discovery of rows of rectangular, low earthen mounds which were foundational platforms for multi-room structures. Larger dimensions and a different organization of space were identified in the central zone, pointing to a building of special status. On the southeastern edge of the settlement, a concentration of metallurgical remains was confirmed: broken crucibles with traces of alloy, pieces of slag as a byproduct of smelting, and fragments of molds and finished items. This set of findings is typical for workshops where smelting and casting took place, but also repairing, recycling, and standardizing production.
Urban logic on the steppe
Semiyarka shows a grid that at first glance seems familiar from other prehistoric centers: long, rectilinear embankments divide the space into "parcels," and housing units are lined up in rows. Although the building material is modest, probably earth-and-wood, the orderliness is distinct. Such a picture differs from the diffuse, seasonal habitats more often recorded on the steppes, and approaches the urbanism we associate with "traditionally urban" areas of the ancient world. Besides construction being standardized, it seems the division of space was also functional: residential units are grouped into blocks, while the industrial zone is located downwind and along natural communications.
Comparisons with other Late Bronze Age sites show just how much of an exception Semiyarka is. An area of about 140 hectares – about 346 "English" acres – makes it the largest known planned settlement of its kind in the region. This directly ties into the debate about whether steppe communities could develop "city" institutions without monumental stone architecture. Semiyarka suggests the answer is affirmative: the criteria of a functional city – division of labor, a central meeting place, and a specialized industrial zone – are clearly recognizable here.
Tin bronze metallurgy: technology, logistics, and organization
Tin bronze – an alloy of copper with tin – requires precise technological supervision. Suffice it to mention that changes in the proportion of tin alter the hardness, brittleness, and melting point of the alloy. Raw material for tin is relatively rare and usually distant from consumer centers, so a stable supply network is necessary. In Semiyarka, precisely that combination of indicators was found which experts have long wished to see in one place: crucibles and molds, slag as smelting waste, raw materials, and finished items, all within a separate "industrial" zone at the edge of the settlement. This concentration points to production on a large scale and organizational mechanisms that supervised the flow of raw materials and standardized procedures.
The logical conclusion is that the settlement used the proximity of the Altai copper and tin deposits. The Irtysh, as an important river axis, connected the north and south and opened exchange channels towards the east and west. In this way, resources, knowledge, and demand could meet in Semiyarka. Such supply systems presuppose social mechanisms of control, probably also a hierarchy in which part of the community was in charge of procurement and processing, and part for distribution and trade. The strength of the place stemmed precisely from this synchronization of functions.
Culture and chronology: a place in the Andronovo horizon
Pottery and other findings point to linking Semiyarka with the Cherkaskul and Alekseyevka–Sargary cultural complexes. These sets are often classified into the wider Andronovo horizon, a large cultural domain of the Late Bronze Age of Northern and Central Eurasia. Preliminary estimates place the beginnings of the settlement around 1600 BC, with possible phases of expansion and remodeling. Semiyarka, therefore, emerged in a period when metallurgy and long-distance exchange networks were already developing intensively, and precisely such circumstances favored the creation of permanent centers.
It is important to emphasize that the "city on the steppe" does not negate mobility, but complements it. Seasonal movements and pastoralism did not disappear but were obviously coordinated with the needs of a permanent operation. This is empirically convincing: a permanent industrial zone needs supplies of fuel, raw materials, and labor; for their delivery and sustenance, flexible but reliable mobile networks are desirable. Semiyarka shows that these two logics – mobility and anchoredness – could coexist and create a sustainable system.
How researchers "read" the city
The field team combined geophysical methods (magnetometry and related techniques), drone imaging, and selective excavations. Geophysics enabled the recognition of rectilinear embankments and large structures without extensive digging, while sondages gave cross-sections of walls, floors, and hearths, and samples for laboratory processing. In the metallurgical zone, numerous examples of crucibles with preserved alloy droplets and a hardened film of metal on the inner walls were documented, as well as diverse types of slag. Additionally, fragments of molds and finished items were collected, complementing the technological story.
Laboratory analyses are focused on the chemical composition of remains and the mineralogy of slag. They help in reconstructing the smelting technique and linking raw materials with possible sources. Although future research will bring more detailed results, deposits in the Altai are already imposing themselves as the most obvious source of tin and copper. Comparisons with findings from other regions show that the scale of the industrial area in Semiyarka is unusually large, which is an additional argument for a centralized operation.
Daily life and social organization
Rectangular, multi-part houses suggest modular construction and standardized floor plans. Some spaces likely served as residential units, others as storage and smaller workshops. The layout of "streets" and rows of houses points to predictable zones of movement – an important feature of a space where work, raw material delivery, and product removal are coordinated. The central building differs in dimensions and position and could have had a ceremonial or administrative function. All this together implies the existence of social roles and responsibilities, from supervising production to deciding on exchange.
Material remains from housing units – pottery, tools, small metal objects – show a repertoire of daily life that was both practical and sufficiently standardized to be easily maintained. This suggests the stability of supply chains and the transmission of knowledge. In such systems, knowledge about metallurgy, fuel procurement, and furnace maintenance is transmitted within the community, but also through exchange with other groups – making Semiyarka an important point in the wider cultural landscape.
Trade and networking: why the location above the Irtysh is key
The position above the Irtysh is not only picturesque but also strategic. The river is a key communication axis connecting the regions of Siberia with the south and west, and the lowlands around it favored the movement of people and goods. In this context, Semiyarka made sense as a center for gathering raw materials and distributing finished products. The movement of items can also be tracked by chemical "signatures" – alloy compositions and impurities sometimes point to specific ore sources, and precisely such observations increasingly link Semiyarka with Altai deposits.
The broader picture of exchange also includes contacts with neighboring cultural groups. Findings of pottery and types of objects suggest contacts with nearby groups of the Andronovo circle. It is possible that agreements were made, goods exchanged, and rituals held in Semiyarka which strengthened inter-community ties. The industrial zone was not isolated in this: its effect was easily felt in everyday life – from tools that changed the labor economy to ornaments that shaped statuses and identities.
Open questions and research plans
Despite the abundance of data, numerous questions remain open. The duration and rhythm of settlement have yet to be specified by a series of absolute dates. It is not entirely clear if all housing units were contemporaneous or if they were arranged in phases. Nor is it clarified if metallurgy techniques changed over time – which differences in slag composition and metal traces in crucibles might indicate. Future research will also focus on environmental aspects of production: fuel consumption, water management, and waste handling.
Bioarchaeological analyses will also contribute: plant and animal remains will help reconstruct diet and economy, and isotopic measurements can show patterns of population and animal mobility. Establishing such a set of analyses will be key to understanding how the "city on the steppe" maintained a balance between local resources and imported materials, and how this influenced social dynamics.
Semiyarka in the wider Eurasian framework
In relation to the most famous prehistoric centers, Semiyarka is special due to its location between forest-steppe and steppe zones and its direct link with Altai ores. Similarities with other sites of the Andronovo circle are seen in standardized floor plan solutions and rows of residential units, but the separated industrial zone and the scale of the place make it almost unique. Because of this, Semiyarka occupies an important place in the debate about the genesis of the "city" outside major river civilizations. If we define a city functionally – through division of labor, a central space, and specialized production – then Semiyarka meets the key criteria.
The discovery also has methodological importance. It shows how powerful drones, geophysics, and targeted excavations are when applied together: it is possible to gain insight into the whole without destructive interventions, while collecting enough material for precise scientific analyses. Thanks precisely to such an approach, future campaigns will answer questions about duration, construction phases, technological changes, and social organization more quickly.
Where to follow new findings
The discovery was presented on November 18, 2025, and has already sparked great interest in the expert and wider public. At the time of writing, December 6, 2025, detailed summaries of results, aerial photos, and depictions of the industrial zone are available, as well as popular science articles contextualizing the findings. As the project progresses, additional technical appendices and catalogs of findings, as well as the expansion of databases on metallurgical traces and ceramic types, are expected. For up-to-date information, it is worth following official publications of universities and journals, as well as specialized portals dedicated to the archaeology of Eurasia.
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