eli5: Why were some ancient cities like Palmyra and Machu Picchu left to ruin and fall apart over hundreds of years instead of being repopulated?
In: 1677
Large ancient cities rely upon the local infrastructure and farmland to feed the city population, if you can’t grow enough food and transport it to the city, then the population of the city can’t be sustained and it will be abandoned.
Cities are really costly to maintain, and the benefits of a city only manifest when you have a thriving and advanced society. You need a ton of people *not* living in the city to feed the people in the city.
But they aren’t actually great for like… basic survival. So whenever you have any kind of societal collapse people tend to leave the cities first because they need to go grow food or something. That’s a lot easier to do in the countryside.
So the population of the city just falls and falls. And by the time said society recovers to the point they can maintain a city in the first place generally they have founded a new city that’s already thriving so there’s no point to move back anyway or they have lost the knowledge about how to maintain the cities infrastructure in the first place. Keep in mind it basically takes only a single generation for all the knowledge to be lost, even if you have written texts.
Another option is that the city is never fully abandoned, like Rome. But again, it’s so expensive to maintain that infrastructure that without a large enough population it falls into ruin. You even have people dismantling old building because they need to build something else. And for us it’s easy to go “omg how could you do that to something so important!” but like…dude needed those bricks to make a house so his family didn’t freeze in the winter.
Honestly, the same thing happened/is happening in the US rust belt.
It’s normally because the conditions that led to that place being attractive to settle changing. For instance in the Fertile Crescent, the rivers that initially made the region so fertile made the land so salty that nothing would grow. Watch The Fall of Civilizations on YouTube.
there are a lot of other factors that determine a cities ability to recover from major events (war, famine, disease, natural disaster, political instability), but ill stick to what i think is most important:
i think a lot of it comes down to geography. a city in a central trade route, near a lot of resources, maybe part of a large system of governance, is a city that well most definitely be rebuilt and repopulated over time, even if a large portion of the population is wiped out or displaced. the accessibility of resources pretty much determines a city’s value to the people in it and the people running it.
cities outside of resourceful areas are much more susceptible to the aftermath of major events. what’s left of these cities isn’t likely to be repopulated by surviving members, or not worth claiming by opportunistic conquerors.
its the reason why some cities are still active after thousands of years of conquest and disaster and death and being passed back and forth, whereas other cities might have turned into ruins after a blip of troubles.
I went to Machu Picchu last April, and the reason for it being left alone was that the Spanish came through and killed a bunch of the “smart” people. In the Inca territories, the way you got status was by being smart, having knowledge. If you were of higher rank due to your education, the king would give you gold to wear on your ears (earrings) that stretched out the earlobes. The Spaniards were able to identify upper class people by their ears and kill them to suppress dissent when they came in to take resources. As the Spaniards took over Peru, Machu Picchu was intentionally abandoned, the natives destroyed the trail leading to it. It’s located in an area that’s difficult to access, so the area was left alone until Hiram Bingham rediscovered it.
You could well ask the same about Detroit.
Economic factors and changes in natural resources mean that a location no longer has the appeal it once did, so citizens move away.
Once that happens you have fewer and fewer people supporting a large infrastructure, which puts more strain on the city. At that point you either watch the inevitable decline or you find some new reason for people to stay.
There are a lot of good answers here about how cities are high maintenance and can’t survive unless they are constantly maintained, but let’s look at the bigger picture. Let’s say you’ve got a city that was abandoned by a civilization as it collapsed. A hundred years go by. A new civilization has taken over and they have the resources to reoccupy the city. That’s a whole bunch of paved roads and perfectly usable buildings just sitting there. Why would they choose not to reoccupy it?
That comes down to why the city was important in the first place, and whether it’s still relevant once it can be reoccupied. If a city is built around a finite natural resource, such as an oasis, and that oasis dries up, that’s pretty much the end of that city forever. If it was built along a river and the course of the river changes, same thing. And it’s not just geological factors: trade routes can change, bypassing cities that used to be trading hubs, or advances in technology can render a city obsolete by making its primary industries useless.
So basically, there are two things that have to happen for a city to be reoccupied: the current civilization in that area needs to be able to reoccupy and it needs to have a good reason to do so. The city’s location needs to be worth the effort of rebuilding.
One reason is the city didn’t grow organically from the needs of the society.
If it’s a cultural/religious center it may have been built in a location due to aesthetics or geographic location (inaccessible, or perhaps central).
It’s not at a location like a river with lots of trade traffic, or a pass through some mountains, or by a great lake or coast.
So if the powers that “want” the city in that unusual location, basically as a flex, fall out of favor or power there is no incentive for people to build there again.
Machu Picchu wasn’t really a city so much as an Imperial estate. It had some significance to the Incan rulers, but exactly what this was isn’t known.
It was abandoned when Spanish invasions of Incan territory put stress on their government, and never recolonized because it had existed to serve the Incan rulers, and there were no more Incan rulers. The location wasn’t really suited for any other purpose, like trade or agriculture or mining
Palmyra has a long history stretching all the way back to the stone age. It actually still is populated today, although it’s not exactly a major city. People lived (and still live) at Palmyra because there’s water…it’s an oasis in the middle of the Syrian desert. But Palmyra’s heyday happened when lots of trade was occurring across the region….it’s a convenient stop on the trade routes between the Eastern Mediterranean and Mesopotamia, and located in a sort of no-man’s land between the Roman and Persian empires.
So Palmyra got very wealthy off trade, and was able to maintain some independence…at least until Rome sacked it and destroyed it. But it was too convenient a spot to remain empty forever (unlike Machu Picchu) and so eventually the Romans rebuilt it as a smaller settlement. It survived off trade for longer, but the Timurids sacked it in 1400 and after that it was basically just a village. The reason it never grew back into a city is probably because of shifting patterns of trade. Not long after this time, overland trade between Europe and Asia shifted more to seaborn trade as European sailors started sailing around Africa. As a result, there was no longer a strong economic reason to rebuild the city again and it remained a village.
This is the usual story with abandoned cities. They are usually repopulated if the original reason that they were built is still there. But if whatever driving motivation goes away, a destroyed city is often not resettled.
I just thought i would through this out: Machu Picchu is not ancient, merely exotic and old (from our perspective). It was merely built 600 years ago.
It seems incredible, but is actually fairly modern.
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