Ancient city Mohenjo-daro is centuries older than thought
By Jordan Joseph
Earth.com staff writer
Researchers have found that Mohenjo-daro, an ancient city in what is now southern Pakistan, is older than archaeologists believed, with a major city wall dated to around 2700 to 2600 BCE.
That earlier date pushes one of the first great cities along the Indus River in South Asia deeper into the past and changes when its urban story begins.
Buried wall clues
At the base of the western wall, buried mudbrick preserved the earliest clear sign that Mohenjo-daro’s city-building had begun.
From that evidence, the Sindh Directorate General of Antiquities & Archaeology (DGAA) documented a first wall that stood several generations earlier than expected.
That pushes the city’s known beginnings back before its better-known urban peak and gives its rise a longer timeline.
Even so, a single wall cannot tell the whole story of how Mohenjo-daro grew, which leaves the larger city waiting to come into view.
A city planned
Streets, house blocks, and raised platforms show that Mohenjo-daro was never a loose village that simply kept spreading.
Across 593 acres in Sindh, southern Pakistan, the ruins at the UNESCO World Heritage site preserve one of South Asia’s earliest large cities.
At its peak, about 40,000 people lived there in brick neighborhoods laid out with a level of order rare for the time.
Planning on that scale makes the older wall date harder to dismiss as a local oddity rather than part of a city.
Water ran everywhere
Water shaped daily life as much as walls did, and Mohenjo-daro’s plumbing still looks startlingly modern.
More than 700 wells fed homes, baths, and drains, moving clean water inward and waste away.
Builders used baked brick, tight joints, and sloped floors so dirty water could flow instead of soaking walls.
Such infrastructure points to shared rules, skilled labor, and civic oversight, not a town stumbling into urban life.
Growth in stages
Growth did not stop with that first barrier, because the western enclosure kept changing as the city gained size and complexity.
Later layers showed rebuilding through the city’s mature centuries, when denser neighborhoods and larger public works were taking hold.
“The walls were expanded and maintained until around 2200 BCE and possibly even longer,” the DGAA said in the same statement.
Seen over time, the wall becomes a marker for urban growth, not just a striking ruin beside a large, raised mound in the city’s western district.
Why timing matters
For years, many archaeologists placed Mohenjo-daro’s rise around 2500 BCE, when its grander public spaces became easier to see.
Finding a major wall slightly earlier shows the city did not appear all at once in finished form.
Archaeologists call that older stage the Kot Diji phase, an earlier stretch of Indus settlement building before the classic urban peak.
Seen that way, Mohenjo-daro looks less like a sudden arrival and more like a city that grew by building.
What still hides
Only about one-third of the ruins has been excavated since work began there in 1922.
Much of the city’s earliest story still sits below later rebuilding, salt damage, and a stubbornly high groundwater level.
Even so, deep coring under the wall found older pottery, which hints that settlement began before that first known fortification.
Buried depth leaves room for another surprise and warns against treating that first wall as the city’s true beginning.
An unclear ending
Abandonment still sits in the dark, and Mohenjo-daro’s end around 1800 to 1700 BCE remains hard to explain.
Stories about invasion or massacre keep returning, but evidence for organized warfare across Indus cities remains thin.
Scattered skeletons at Mohenjo-daro do not line up neatly with one final disaster, which weakens any single-cause ending.
So, the earlier wall date matters even more, because beginnings are clearer here than endings.
Drought across cities
Climate now offers the strongest broad explanation for why large Indus cities thinned out instead of recovering.
A 2025 study traced four long droughts that likely squeezed rivers, fields, and urban food supplies.
Because those dry spells lasted for decades, communities had time to adapt but less chance to rebuild old city life.
Even that idea leaves room for politics, disease, and migration, but it favors slow strain over sudden collapse.
Ruins under threat
Today’s ruins face a different threat, because salt-rich groundwater and weather attack brick once protected by burial.
Conservation teams must learn what stands where, when it was built, and which areas can still survive new digging.
“Future investigations will trace the plan of the city wall around the Stupa Mound in order to try and locate gateways,” the DGAA said in the same statement.
Saving Mohenjo-daro now depends on treating dating as a preservation tool, not just an academic timeline.
A longer history
Mohenjo-daro now appears to have a longer development, where organized building, water control, and social coordination developed earlier than expected.
In turn, that longer history sharpens the mystery of its decline and raises the stakes for protecting what still lies buried.
Ancient city Mohenjo-daro is centuries older than thought
By Jordan Joseph
Earth.com staff writer
Researchers have found that Mohenjo-daro, an ancient city in what is now southern Pakistan, is older than archaeologists believed, with a major city wall dated to around 2700 to 2600 BCE.
That earlier date pushes one of the first great cities along the Indus River in South Asia deeper into the past and changes when its urban story begins.
Buried wall clues
At the base of the western wall, buried mudbrick preserved the earliest clear sign that Mohenjo-daro’s city-building had begun.
From that evidence, the Sindh Directorate General of Antiquities & Archaeology (DGAA) documented a first wall that stood several generations earlier than expected.
That pushes the city’s known beginnings back before its better-known urban peak and gives its rise a longer timeline.
Even so, a single wall cannot tell the whole story of how Mohenjo-daro grew, which leaves the larger city waiting to come into view.
A city planned
Streets, house blocks, and raised platforms show that Mohenjo-daro was never a loose village that simply kept spreading.
Across 593 acres in Sindh, southern Pakistan, the ruins at the UNESCO World Heritage site preserve one of South Asia’s earliest large cities.
At its peak, about 40,000 people lived there in brick neighborhoods laid out with a level of order rare for the time.
Planning on that scale makes the older wall date harder to dismiss as a local oddity rather than part of a city.
Water ran everywhere
Water shaped daily life as much as walls did, and Mohenjo-daro’s plumbing still looks startlingly modern.
More than 700 wells fed homes, baths, and drains, moving clean water inward and waste away.
Builders used baked brick, tight joints, and sloped floors so dirty water could flow instead of soaking walls.
Such infrastructure points to shared rules, skilled labor, and civic oversight, not a town stumbling into urban life.
Growth in stages
Growth did not stop with that first barrier, because the western enclosure kept changing as the city gained size and complexity.
Later layers showed rebuilding through the city’s mature centuries, when denser neighborhoods and larger public works were taking hold.
“The walls were expanded and maintained until around 2200 BCE and possibly even longer,” the DGAA said in the same statement.
Seen over time, the wall becomes a marker for urban growth, not just a striking ruin beside a large, raised mound in the city’s western district.
Why timing matters
For years, many archaeologists placed Mohenjo-daro’s rise around 2500 BCE, when its grander public spaces became easier to see.
Finding a major wall slightly earlier shows the city did not appear all at once in finished form.
Archaeologists call that older stage the Kot Diji phase, an earlier stretch of Indus settlement building before the classic urban peak.
Seen that way, Mohenjo-daro looks less like a sudden arrival and more like a city that grew by building.
What still hides
Only about one-third of the ruins has been excavated since work began there in 1922.
Much of the city’s earliest story still sits below later rebuilding, salt damage, and a stubbornly high groundwater level.
Even so, deep coring under the wall found older pottery, which hints that settlement began before that first known fortification.
Buried depth leaves room for another surprise and warns against treating that first wall as the city’s true beginning.
An unclear ending
Abandonment still sits in the dark, and Mohenjo-daro’s end around 1800 to 1700 BCE remains hard to explain.
Stories about invasion or massacre keep returning, but evidence for organized warfare across Indus cities remains thin.
Scattered skeletons at Mohenjo-daro do not line up neatly with one final disaster, which weakens any single-cause ending.
So, the earlier wall date matters even more, because beginnings are clearer here than endings.
Drought across cities
Climate now offers the strongest broad explanation for why large Indus cities thinned out instead of recovering.
A 2025 study traced four long droughts that likely squeezed rivers, fields, and urban food supplies.
Because those dry spells lasted for decades, communities had time to adapt but less chance to rebuild old city life.
Even that idea leaves room for politics, disease, and migration, but it favors slow strain over sudden collapse.
Ruins under threat
Today’s ruins face a different threat, because salt-rich groundwater and weather attack brick once protected by burial.
Conservation teams must learn what stands where, when it was built, and which areas can still survive new digging.
“Future investigations will trace the plan of the city wall around the Stupa Mound in order to try and locate gateways,” the DGAA said in the same statement.
Saving Mohenjo-daro now depends on treating dating as a preservation tool, not just an academic timeline.
A longer history
Mohenjo-daro now appears to have a longer development, where organized building, water control, and social coordination developed earlier than expected.
In turn, that longer history sharpens the mystery of its decline and raises the stakes for protecting what still lies buried.
Ancient city Mohenjo-daro is centuries older than thought
