Archaeologist Karim Sadr discovered a forgotten large city near Johannesburg, South Africa. The investigation is still in full swing, but NEMO Kennislink is talking to him about his findings so far via a cracking telephone line.
There are a lot of ruins in the Suikerbosrand nature reserve near Johannesburg. It was therefore known that people have lived here and that the civil war put an end to that habitation two hundred years ago. Professor Karim Sadr (Witwatersrand University, South Africa) wanted to know more about this and started his archaeological research into the ruins ten years ago.
Seeing through plants
First, Sadr and his students created a database based on Google Earth images of the area. But because the vegetation obscured too much of the view, LIDAR came into the picture. With this laser technology you can 'see' through the vegetation from the air.
“LIDAR works like radar, but with laser light instead of radio waves. You fly the device over the area and emit laser light beams. When they hit something, it bounces back and that distance is measured in time,” explains Sadr. With this, the scientists saw four times as many buildings as via Google Earth. Where they were still bothered by vegetation with Google Earth, LIDAR made it possible to look through it and see the size of this city.
Last year, the archaeologist started analyzing the LIDAR data, and what slowly unfolded to him then exceeded all expectations. “The stories about an ancient city were known and the ruins visible, but for the first time we have now been able to map how urbanized this area has been. They weren't just scattered buildings here and there, as we thought, it was the largest city in the region.”
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The population group living in this area at the time, the Tswana community, was organized into politically independent kingdoms. These kingdoms consisted of a capital with land around it. “Nowhere in the east and south of South Africa was a city of this size. Only further west can you find such cities at the beginning of the nineteenth century," says the archaeologist.
The once thriving city was destroyed during wars in the early 1800s caused by climate change and colonialism. It got colder and colder, making it more difficult to farm. Farmers from the south and new British settlers moved inland from the coastal areas in search of better land. Zulu king Shaka Zulu also expanded his kingdom from the southeast. This caused a domino effect, with the fleeing humans and marauding armies moving further and further inland.
Sadr:“Everyone fought with everyone. A large group of Ndebele came from the south and settled near the city with a strong army between 1824 and 1827. They caused a lot of trouble and partially destroyed the city. We do not know what happened to the population left behind, but we do know that this meant the end for the prosperous city.” However, settlers claimed to have found empty land, allowing them to take it and found the mining city of Johannesburg.
Leaving in haste
However, the houses destroyed during the wars turned out not to be the oldest buildings. Sadr has found stone walls dating back to the fifteenth century:“Until about 1550 the farms were scattered here and there, but then the architecture changed and the inhabitants started building homesteads, clustered together on the hill.”
The archaeologists have counted a total of nine hundred homesteads, but they do not yet know whether they were also inhabited at the same time. This makes it difficult to estimate the population of the city, Sadr says. “On average, between ten and twenty people lived in homesteads, which would mean a population of nine to eighteen thousand people. I keep my estimate at ten thousand inhabitants during the height of the city.”
An important question is whether the wars destroyed the entire city at once or whether people continued to live there. “You can see from the remains that the people left in a hurry. They have left behind many things, such as pots, pans and utensils. This is evident from the three homesteads that we have been able to investigate so far.” But because the archaeologist has also found very simple houses that do not resemble the richer architecture of the homesteads, he thinks that people continued to live there after the destruction.
Democracy
A homestead consisted of a yard with the main building and outbuildings. Here lived the male head of a family, with his (sometimes as many as fifteen) wives. They all had their own house in the yard. The largest homestead, that of the king, had a central meeting place. Sadr has also found such a large open space in this city. “It is a natural hill where the king could confer and look out over the city.”
There was a strong hierarchy within the Tswana community. The king appointed chieftains for each district, and the male heads of the families fell among the chieftains. “So these grown men were all politicians. They negotiated everything with each other, the king did not make decisions on his own. It was a very democratic system. The young and mature men who were lower in the hierarchy were tending the herds. There was no religious center, but some priests and medicine men must have lived there. In addition, we found tools, which indicate craftsmen. The women did all the work on the land and took care of the household.”
In the Tswana community you were rich if you had a lot of cattle. The archaeologists do not yet know how many cattle there must have been in the city, but they do know that the buildings were large and of rich architecture. “Livestock had to be protected and several buildings indicate the presence of a large herd. This is further proof that the city was so rich that it had no equal in this area.”
The value of livestock is also reflected in the funeral rites of the Tswana community. “There are no marked graves or cemeteries in the city. The custom was to bury the women behind the house and the men under the fence around the stockyard. We did find a tower near the king's central stockyard. We don't know what its function is yet, but it could be a marker of elite graves.”
Further investigation
The city has now been mapped, but there are still many big questions open to Sadr and his students. “We want to know how many people lived here, who belonged to the elite and where they lived. We also do not yet know which part of the city is old and which part is young, and whether it has been abruptly abandoned. We already have some assumptions, but we have yet to find the evidence for this. We will be working on that for a few more decades.”To be continued…