Mohenjo-daro

Mohenjo-daro is an archaeological site in Sindh province, Pakistan, near the Indus River. About 4,500 years ago it was one of the largest cities in the world. It belonged to the Indus Valley Civilisation, also called the Harappan Civilisation after Harappa, the first of its cities to be studied.

The Indus Civilisation was one of the earliest civilisations, living at the same time as ancient Egypt and Mesopotamia. At its height it covered a larger area than either, stretching across much of today's Pakistan and northwestern India. Mohenjo-daro and Harappa were its greatest cities, together with others such as Dholavira, Ganeriwala and Rakhigarhi.

We do not know the city's ancient name. Mohenjo-daro is a modern Sindhi name usually translated as "Mound of the Dead". Because the Indus script has not been deciphered, everything we know about the city comes from its buildings and objects, not from its own written records.

The city stood on a ridge in the flat, fertile flood plain of the lower Indus, about 28 kilometres from the modern town of Larkana. The river brought water and rich silt for farming, and it was also a highway for boats carrying goods up and down the valley and toward the Arabian Sea. The same river could be dangerous: its floods were powerful, and over thousands of years it has changed course many times. Life at Mohenjo-daro was always a balance between using the Indus and protecting the city from it.

The city had two main parts. To the west rose a high artificial mound, about 12 metres tall, that archaeologists call the Citadel. To the east lay a much larger area, the Lower Town, where most people lived and worked. Both stood on huge platforms of mud brick and earth that raised them above the floods of the Indus.

Main streets ran roughly north–south and east–west, dividing the Lower Town into large blocks. Smaller lanes led off them. Most houses had a courtyard in the middle, rooms around it, and doors opening onto side lanes rather than the busy main streets. Some houses had a second floor, reached by stairs.

Water was everywhere. Archaeologists have found more than 700 wells, lined with wedge-shaped bricks, so that many households had a well nearby. Many houses had a bathing area with a sloping floor and a toilet. Waste water flowed through clay pipes into brick drains along the streets, which were covered with bricks or stone slabs and had openings for cleaning. Few cities anywhere had such a system for thousands of years afterwards.

Different kinds of buildings were mixed together in the Lower Town. Large houses with many rooms stood near small ones, and workshops for beads, shell or pottery were found among homes. Some blocks had wide streets with brick drains running along both sides, while narrow lanes wound between houses. The city was not perfectly uniform like a chessboard, and it changed over time, but it clearly followed a plan that people maintained for many generations.

The most famous building is the Great Bath on the Citadel. It is a rectangular pool about 12 metres long, 7 metres wide and 2.4 metres deep, with steps at each end. Carefully fitted bricks were set in gypsum mortar and backed by a layer of bitumen, a natural tar, to keep water in. A colonnade and small rooms surrounded it, and a large drain could empty it.

Because later South Asian religions give great importance to bathing and purity, many archaeologists think the Great Bath was used for ritual washing. But this is an interpretation; no inscription explains it.

Next to it is a massive building with a grid of brick foundations that Mortimer Wheeler called the "Great Granary", imagining carts unloading grain there. Later archaeologists such as Jonathan Mark Kenoyer pointed out that no grain was found, and suggested calling it the "Great Hall". Other large structures include a "Pillared Hall", perhaps a meeting place, and the so-called "College", a complex of many rooms. All these names were given by excavators and may not match how the buildings were really used.

Mohenjo-daro was built mostly of fired brick, which is stronger and more water-resistant than sun-dried mud brick. Indus bricks across hundreds of kilometres share similar proportions, about 1 : 2 : 4 in thickness, width and length, a sign of shared building standards. Builders laid them in patterns that made walls strong, and used mud brick for platforms and fill.

The city seems to have been laid out deliberately from an early stage. Wells and drains were planned with the streets, and later rebuilding usually followed the old lines. Over centuries, as floods deposited silt and houses were rebuilt, the city rose on its own debris; Wheeler believed it had been flooded and rebuilt several times.

Much of the city lies below the present water table. The earliest levels have never been fully reached, so archaeologists do not know how or exactly when the settlement began. A core-drilling survey in 2015 suggested that the ancient city extended beyond the excavated area.

The skill needed to fire millions of bricks, plan drainage and organise labour points to strong community organisation. Yet no palace, royal tomb or grand temple has been clearly identified, which makes Mohenjo-daro very different from contemporary cities in Egypt and Mesopotamia.

The people of Mohenjo-daro grew wheat and barley, kept cattle, including humped zebu, and wove cotton, one of the earliest known uses of the plant for cloth. Craftspeople made fine pottery, shell bangles, stone and metal tools, and long carnelian beads drilled with remarkable precision. Some parts of the city seem to have specialised in particular crafts, such as shell-working.

They used standard cubical weights of chert, following a system that doubled in the smaller units and then became decimal in the larger ones. A fragment of a shell scale found at the city has carefully spaced marks. Such standards made fair trade possible across a huge area.

Trade reached far beyond the Indus. Indus seals, beads and weights have been found in Mesopotamia, the Persian Gulf and Central Asia. Mesopotamian cuneiform texts mention a land called Meluhha that supplied carnelian, timber and other goods; most scholars identify Meluhha with the Indus region, though this is an inference.

Houses differ in size, so there were richer and poorer people. But the wide access to wells, bathrooms and drains has struck many archaeologists as unusually even. Children's toys, dice, and figurines of animals and people give glimpses of daily life and play.

Thousands of small square seals, carved mostly from steatite, have been found at Indus sites. Most show an animal, most often a one-horned bull-like creature that archaeologists call a "unicorn", with a short line of signs above. They were probably used to stamp clay tags on goods and may have identified owners, officials or groups.

The "Priest-King" is a steatite bust about 17.5 centimetres high, found in 1927. It shows a bearded man wearing a headband and a robe decorated with trefoil patterns that once held red paste. The name is a modern guess with no firm basis; the figure may represent an important community member or ancestor. It is now in the National Museum of Pakistan in Karachi.

The "Dancing Girl" is a bronze figurine about 10.5 centimetres high, found in 1926 and made by lost-wax casting. It shows a young woman standing confidently with many bangles on one arm. Whether she was a dancer is unknown. She is now in the National Museum, New Delhi.

The so-called Pashupati seal shows a figure seated cross-legged surrounded by animals. John Marshall suggested it was an early form of the Hindu god Shiva; others see a yogic posture, and many scholars caution that such links to later religions cannot be proven. Female terracotta figurines have been read as signs of a mother-goddess cult, but their meaning is also debated.

After about 1900 BCE the great Indus cities declined. At Mohenjo-daro, later levels show poorer construction, houses built over streets, and less careful maintenance. By around 1700 BCE the city was largely abandoned, though people continued to live in smaller settlements across the region.

There was no single catastrophe. Most scholars now point to a combination of causes: changes in the monsoon and a drier climate, shifts in river courses, flooding and silting, strains on farmland, and a breakdown in long-distance trade with Mesopotamia. Gregory Possehl, for example, emphasised gradual processes such as repeated minor floods and overuse of land rather than one great mud flood.

Much later, in the early centuries CE, a Buddhist stupa was built on top of the Citadel mound. Its ruins were what first drew archaeologists' attention to the site in the twentieth century.

The end of the great cities did not mean the end of the people. In the Late Harappan period, many communities moved east and south, toward the Ganges plain and Gujarat, living in smaller villages. Writing on seals and standard weights largely disappeared, and long-distance trade shrank, but farming, crafts and some traditions continued. Archaeologists therefore describe the change as a transformation of society rather than the sudden disappearance of a population.

In 1919–1920 and again in 1922, R. D. Banerji of the Archaeological Survey of India visited the mound to study the Buddhist stupa and found much older remains beneath it. In 1924 the Survey's director, John Marshall, announced to the world that Harappa and Mohenjo-daro belonged to a previously unknown ancient civilisation. Scholars soon noticed that similar seals had been found in Mesopotamia, which helped date the cities to the third millennium BCE.

Large-scale excavations followed under K. N. Dikshit, Marshall and Ernest Mackay in the 1920s and 1930s. Mortimer Wheeler dug on the Citadel in 1950, and George Dales led the last major excavation in 1964–1965. After that, digging was largely stopped because exposed walls were decaying, and work turned to surveys, documentation and conservation, including German and Italian projects led by Michael Jansen and Maurizio Tosi in the 1980s.

The Partition of India in 1947 divided the finds. Mohenjo-daro lay in Pakistan, but many objects were in Delhi. The collections were split between the two countries, sometimes literally bead by bead. Pakistan received the Priest-King and India kept the Dancing Girl, though accounts differ on when and how the Priest-King reached Karachi.

Early interpretations were shaped by comparison with Mesopotamia. In his first reports Marshall even spoke of an "Indo-Sumerian" civilisation, before recognising that the Indus cities represented a distinct culture of their own. The discovery overturned the assumption, common at the time, that the history of South Asian civilisation began with the Vedic period, and pushed the region's urban history back by more than a thousand years.

Mohenjo-daro was inscribed on the UNESCO World Heritage List in 1980, the first site in South Asia to be listed, and an international campaign to protect it began the same year. The greatest threat is salt. Groundwater rises into the bricks, and as it evaporates in the hot climate, salt crystals grow inside them and make them crumble.

Flooding and erosion are further dangers, and some earlier repairs used unsuitable materials that damaged original walls. Responsibility for the site passed to the government of Sindh in 2011, and Pakistani archaeologists have warned that without better care the ruins could suffer severe loss. In 2014 plans to hold a festival opening ceremony on the site caused a public outcry among archaeologists.

Conservation raises hard choices: whether to rebury exposed areas to protect them, how much to rebuild, and how to balance tourism with preservation. The decision to stop large excavations shows how archaeology itself can put fragile sites at risk.

Objects from the city are now spread across several museums: the National Museum of Pakistan in Karachi, a site museum at Mohenjo-daro itself, the National Museum in New Delhi, and smaller collections abroad, including the British Museum. A large replica of the Priest-King stands at the entrance to the site, showing how the city has become a symbol of Pakistan's ancient heritage.

Who governed Mohenjo-daro? The absence of obvious palaces, royal burials and depictions of war has led to competing models: a single Indus state, several city-states, rule by merchant or priestly elites, or looser councils. Standardised bricks and weights suggest coordination but not necessarily a centralised king. The debate also touches a broader question in archaeology: whether large-scale urbanism requires a strong ruling class.

Early excavators proposed that the city fell to invading Indo-Aryan peoples. Wheeler pointed to groups of skeletons found in the upper levels as victims of a final massacre and linked them to the Vedic god Indra, called a "fort-destroyer". George Dales argued in 1964 that these skeletons came from different periods and did not represent a single slaughter, and later studies found little evidence of violent attack. Most archaeologists now reject the invasion model as an explanation for the city's end, although questions about the arrival of Indo-Aryan languages in South Asia remain a separate and politically sensitive field of research.

The Indus script consists of several hundred signs, mostly in very short inscriptions averaging only a few signs. Without a bilingual text, many decipherment claims have been made, linking it to early Dravidian, Indo-Aryan or other languages, and some scholars have even questioned whether it encodes language fully. None has won general acceptance.

Names are also debated. Some Indian writers use "Indus–Sarasvati Civilisation", identifying the dried Ghaggar-Hakra river with the Sarasvati of the Rigveda. Geological research suggests the Ghaggar-Hakra was a monsoon-fed system rather than a great glacier-fed river in the Harappan period, and many archaeologists prefer the neutral terms "Indus" or "Harappan".

Much of what we know comes from excavations in the 1920s and 1930s, which removed huge volumes of soil quickly and recorded finds by depth rather than by natural layers. This makes it hard to separate building phases or date individual objects precisely. Later researchers have re-analysed the old records, re-examined walls still standing, and combined them with limited new excavation, surface survey and architectural mapping.

Radiocarbon dating from the Indus region, together with Mesopotamian contexts containing Indus objects, underpins the chronology of the Mature Harappan phase. Studies of animal bones, plant remains and isotopes in teeth have begun to reveal diet, farming and people's movements between regions.

Interpretation remains the central challenge. Terms such as "Citadel", "Granary", "College" and "Priest-King" reflect the assumptions of early excavators who compared the Indus with Mesopotamia or with later Indian traditions. Recent work tries to describe buildings by their form and associated finds first, and to test interpretations against the whole pattern of evidence. Standard syntheses include Jonathan Mark Kenoyer's Ancient Cities of the Indus Valley Civilization and Gregory Possehl's The Indus Civilization: A Contemporary Perspective.