The city of Moenjo-daro,which was one of the largest cities of the Bronze Age (Picture: Quratulain/Cover Media)

One of the ancient world’s great urban centres is much older than previously thought,according to new research which could transform our understanding of how civilisation developed.

Fresh excavations at Mohenjo-daro,in present-day Pakistan,suggest its origins date back several centuries earlier than had been previously established.

Situated along the Indus River in Sindh’s Larkana district,Mohenjo-daro covers more than 620 acres and is thought to have supported up to 40,000 people at its peak – making it one of the largest cities of the Bronze Age.

New radiocarbon dating from excavations carried out between 2025 and 2026 indicates that the site was already occupied during the Early Harappan,or Kot Diji,phase between about 3300 and 2600 BC. That makes the city even older than the pyramids.

New discoveries at the site could reshape understanding of how urban centres developed (Picture: Junhi Han/Cover Media)

Researchers say this challenges the long-held view that urban life in the Indus Valley emerged rapidly around 2600 BC,instead pointing to a more gradual process of development.

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Start your day informed with Metro's News Updates newsletter or get Breaking News alerts the moment it happens.The project,led by Pakistan’s Dr Asma Ibrahim and Ali Lashari along with Dr Jonathan Mark Kenoyer from the University of Wisconsin focused on an area west of the site’s Stupa Mound.Archaeologists re-examined a large mudbrick structure first uncovered in 1950 by Mortimer Wheeler,who had interpreted it as a flood-control embankment. New analysis suggests a different conclusion.Using stratigraphic study and radiocarbon dating,researchers found the structure to be a multi-phase mudbrick city wall,built and expanded over several centuries rather than serving a purely defensive or hydraulic function.Samples from its lowest levels date its earliest construction to around 2700–2600 BC,towards the end of the Early Harappan period.Fresh evidence at Moenjo-daro suggests that the city developed in phases (Picture: Cover Media)Further evidence beneath the wall revealed even earlier settlement activity,including pottery typical of the Kot Diji phase. This indicates the city evolved from an existing community,rather than being constructed from scratch during the later,more developed phase of the civilisation.

Upper levels of the wall show continued construction during the Mature Harappan period,after 2600 BC,when Mohenjo-daro reached its height.Researchers say the wall was expanded and maintained until at least 2200 BC,suggesting long-term planning and resource management.Although the latest findings focus on the city’s earliest phases,Mohenjo-daro has continued to yield discoveries from much later periods.Mohenjo-daro is known for its advanced urban planning,including grid-like streets,standardised baked bricks and sophisticated drainage systems,as well as monumental structures such as the Great Bath.Mohenjo-daro is known for its advanced urban planning,including grid-like streets (Picture: Solophar/Cover Media)However,one of its greatest mysteries remains unsolved: the Indus script,found on seals and tablets,has yet to be deciphered. If and when it is,the story of the city’s emergence could become far more accessible.Without written records,archaeologists rely on physical evidence and scientific techniques to reconstruct the city’s past.The findings mark a shift in understanding the rise of urban life in the Indus Valley,say researchers.