Logistics of a mountaintop city

[Aldarion]

So looking at a city located on a mountaintop or a mountain plateau (think Machu Picchu), how would the city logistics works? Most cities had immediate farmland to provide food, but how could a mountaintop city solve food issues (I already have ideas on water, mind you)? Is there a limit on how high city could be positioned above the plain? And what was the maximum practical size a mountaintop or hilltop city could achieve?

NOTE: We are talking about specifically medieval city here.

 

[ThinkerX]

The best real-world example would be the Inca. From Google:

The population of the Inca capital city of Cuzco at its peak was around 150,000 people. The Inca Empire's population is estimated to have been between 6 and 14 million people before the Spanish arrived in the New World. However, the population plummeted to less than 1.5 million people within 50 years of the Spanish arrival due to disease and warfare

 

[Finchbearer]

Machu Picchu may not have been built in the medieval period, just after, but they would have used more along the lines of ‘medieval technology’, that is when compared to Western Europe, so why wouldn’t you use Machu Picchu as the model? There are pre-medieval era similar high altitude ‘cities’.

As far as population levels go, that would depend on more than just food and water availability. Maybe there is a religious or sacred element to it, such as a passing place for pilgrims. That would attract some wealth into the area for instance. Maybe they export something of worth, wool or textiles perhaps.

With Machu Picchu, despite being at a high altitude there is a lot of rainfall in that area of the world. Maybe the pyramid structure and lots of clever terracing would have provided enough farmland and water resource. I don’t know about the specific crops, but in that part of the world at high altitude, you’re talking lots of starchy carbs, such as potatoes, and animal fat and dairy. Alpacas, llamas, sheep, cows, chickens etc. and herbs that grow at that altitude to flavour things. If food and water are covered, you can pretty much live as long as the politics aren’t too tumultuous.

 

[Aldarion]

Machu Picchu may not have been built in the medieval period, just after, but they would have used more along the lines of ‘medieval technology’, that is when compared to Western Europe, so why wouldn’t you use Machu Picchu as the model? There are pre-medieval era similar high altitude ‘cities’.

As far as population levels go, that would depend on more than just food and water availability. Maybe there is a religious or sacred element to it, such as a passing place for pilgrims. That would attract some wealth into the area for instance. Maybe they export something of worth, wool or textiles perhaps.

With Machu Picchu, despite being at a high altitude there is a lot of rainfall in that area of the world. Maybe the pyramid structure and lots of clever terracing would have provided enough farmland and water resource. I don’t know about the specific crops, but in that part of the world at high altitude, you’re talking lots of starchy carbs, such as potatoes, and animal fat and dairy. Alpacas, llamas, sheep, cows, chickens etc. and herbs that grow at that altitude to flavour things. If food and water are covered, you can pretty much live as long as the politics aren’t too tumultuous.

Thanks! And yes, Machu Picchu is one of the models I had used for the city.

But in this case, it is basically a fortress city built for reasons of security - a retreat for administration, so to speak.

 

[Ban]

Correct me if I am wrong, but access to water seems to be no major concern or constraint in the many, vast Andes cities. Of course, that's partly because they have a temperate climate up there, while in many other places in the world mountain tops are covered in snow, but snow can be melted fairly easily with a fire. I imagine the reason we don't have such cities in Europe is simply because of our differing temperatures and the fact we have no real reason to not simply settle the valleys instead. In South America El Niño and La Niña have to be accounted for, which we have no equivalent of here.

 

[Aldarion]

Correct me if I am wrong, but access to water seems to be no major concern or constraint in the many, vast Andes cities. Of course, that's partly because they have a temperate climate up there, while in many other places in the world mountain tops are covered in snow, but snow can be melted fairly easily with a fire. I imagine the reason we don't have such cities in Europe is simply because of our differing temperatures and the fact we have no real reason to not simply settle the valleys instead. In South America El Niño and La Niña have to be accounted for, which we have no equivalent of here.

Yeah, as I said, water is not what I am concerned with here; food is. I am thinking of including a raised plateau behind the city that would serve as food source to an extent at least.

 

[Ban]

Yeah, as I said, water is not what I am concerned with here; food is. I am thinking of including a raised plateau behind the city that would serve as food source to an extent at least.

In Switzerland herding was famously common, with herders going up and down the mountains with their flocks. If they can sustain valley cities, surely they can sustain mountain cities as well as long as the paths remain traversable. If the mountain has a gentle enough incline you could have your people build terraces in them for various produce. Potatoes, carrots and beets can even be grown in pots and should be hardy enough to withstand the altitude.

 

[Aldarion]

In Switzerland herding was famously common, with herders going up and down the mountains with their flocks. If they can sustain valley cities, surely they can sustain mountain cities as well as long as the paths remain traversable. If the mountain has a gentle enough incline you could have your people build terraces in them for various produce. Potatoes, carrots and beets can even be grown in pots and should be hardy enough to withstand the altitude.

Thanks!

EDIT: I have two options for city now:

https://i.ibb.co/vwsg6VX/map-city-area-colored.png

https://i.ibb.co/9wSfpgv/map-city-area-colored-v2.png

 

[barrowyarrow]

The Inca as mentioned did a lot of terrace farming. They grew a lot of corn and potatoes. Their cities were also supported by a lot of pack animal herders who would have llamas carry goods up and between the mountains. These animals also gave them meat, wool, and fertilizer for their farms. You could also look into the Ural Mountain People or early settlers of the Afghan Mountains. The issue a lot of people run into when writing mountain civilizations is that people who would be called mountain people typically didn't settle on the peaks of the mountains so much as in the lowlands between the mountains. Mountains provide a lot of natural protection from invaders and water run off from them brings a lot of minerals to the soil which creates very fertile farmland.

You could include details in your writing about husbandry of mountain animals like goats or sheep or the mentioned llamas. Maybe characters take note of multi leveled farms as they walk up the winding pathways designed for these pack animals. Or maybe this mountain culture has a lot of other towns and cities that sprung up in the lowlands near them and trade between those towns is what supports the existence of this mountain top city. Just some ideas to chew on.

 

[Aldarion]

The Inca as mentioned did a lot of terrace farming. They grew a lot of corn and potatoes. Their cities were also supported by a lot of pack animal herders who would have llamas carry goods up and between the mountains. These animals also gave them meat, wool, and fertilizer for their farms. You could also look into the Ural Mountain People or early settlers of the Afghan Mountains. The issue a lot of people run into when writing mountain civilizations is that people who would be called mountain people typically didn't settle on the peaks of the mountains so much as in the lowlands between the mountains. Mountains provide a lot of natural protection from invaders and water run off from them brings a lot of minerals to the soil which creates very fertile farmland.

You could include details in your writing about husbandry of mountain animals like goats or sheep or the mentioned llamas. Maybe characters take note of multi leveled farms as they walk up the winding pathways designed for these pack animals. Or maybe this mountain culture has a lot of other towns and cities that sprung up in the lowlands near them and trade between those towns is what supports the existence of this mountain top city. Just some ideas to chew on.

Thanks!

But just to note, this is not an originally mountain culture... rather, retreat to mountains was prompted by need for protection against sea raiders.

 

[barrowyarrow]

Thanks!

But just to note, this is not an originally mountain culture... rather, retreat to mountains was prompted by need for protection against sea raiders.

I see. In that case it might be cool to add stuff like old boats that have been repurposed for structures, or cultural behaviors that are holdouts from when these people used to live closer to the coast.

 

[pmmg]

I dont know the answer to this. But I would think if there is going to be a mountain city, there must be a reason. Either a need for protection, or something like gold found in the rocks creating a draw. In either case, support for the people living there would seem to rely on good roads and trade. The mountain can only offer so much in the way of farm land, so I think it must be borrowed from other places. Maybe they have great stores and have a lot of grain.

I am not sure people just build cities on top of mountains just cause its cool.

I also think, if the city is dependent on trade, anyone gaining control of their supply lines would be able to siege them with some good effectiveness, though they may not be able to get inside.

The very effort of getting the supplies up to the mountain to build structures ought to create the roads for trade.

 

[Prince of Spires]

It's good to differentiate between how large could a random city get and how large could a city that had to sustain itself get. There's a big difference between the two.

Once a city grows beyond a certain size, it will always require imports from other places. How big of course depends on how fertile the land around it is. But ancient Rome relied heavily on imports from across its empire to feed itself. With that it managed to grow beyond a million people.

That can easily be the case for your mountain city as well. If a lot of people have a reason to be there, then human ingenuity and greed will find a way to keep those people fed. They would simply import whatever they are lacking. And, as mentioned, once a city grows beyond several thousand people, it would do so regardless of its location.

What then matters is how many people could a mountain city contain if it had to feed itself. I'm not sure there's a precise answer. Terrace farming could turn a lot of the steeper sections into usable farm land, and grazing animals can provide plenty of food. There is in this little difference between a city in a valley or on a mountain top, except in the direction you walk when you're done working and want to sell your produce.

The main exception is water. It's hard to get water to a mountaintop, while it's easy to get it to a city at the bottom of a valley. You mention you have it sorted out. But even so, I think water is the main limiting factor. People use a lot of it, and there is a difference between simply waiting for the water to flow down a mountain and actively having to carry it up it.

As for the maximum elevation, you're looking at probably 4.000m above sea level, give or take. Much higher, and humans start being affected and you can run into altitude sickness and so on. Though of course, the local population would adapt. But even a city like Lhasa is only at 3700m. We're just not made to live above those altitudes. Already temperature and how well stuff grows is a big factor. You're for instance running into maximum height of the tree-line at those kinds of altitudes (the highest is in Bolivia at 5.200m).

 

[Finchbearer]

But in this case, it is basically a fortress city built for reasons of security - a retreat for administration, so to speak.

Aren’t there thoughts that this is what Machu Picchu was for? More of a retreat for administration as you say. Would you have a Bailey, so to speak, with various farmers, weavers, healers, blacksmiths etc working to keep things running along?

 

[Aldarion]

It's good to differentiate between how large could a random city get and how large could a city that had to sustain itself get. There's a big difference between the two.

Once a city grows beyond a certain size, it will always require imports from other places. How big of course depends on how fertile the land around it is. But ancient Rome relied heavily on imports from across its empire to feed itself. With that it managed to grow beyond a million people.

That can easily be the case for your mountain city as well. If a lot of people have a reason to be there, then human ingenuity and greed will find a way to keep those people fed. They would simply import whatever they are lacking. And, as mentioned, once a city grows beyond several thousand people, it would do so regardless of its location.

Food imports however require either waterways or else railroad. Railroad is obviously beyond the capacity of technologically early medieval society to build, and while there is a river nearby, it is below the city. Plus, the Empire kinda isn't in the situation where it can ensure reliable food supply to the city anyway - it has to be able to fend for itself.

What then matters is how many people could a mountain city contain if it had to feed itself. I'm not sure there's a precise answer. Terrace farming could turn a lot of the steeper sections into usable farm land, and grazing animals can provide plenty of food. There is in this little difference between a city in a valley or on a mountain top, except in the direction you walk when you're done working and want to sell your produce.

The main exception is water. It's hard to get water to a mountaintop, while it's easy to get it to a city at the bottom of a valley. You mention you have it sorted out. But even so, I think water is the main limiting factor. People use a lot of it, and there is a difference between simply waiting for the water to flow down a mountain and actively having to carry it up it.

Yeah, there are terraces, and I am thinking of including a plateau behind the city as well for food production. As for water, there are several spring wells as well as water cisterns collecting rainfall.

As for the maximum elevation, you're looking at probably 4.000m above sea level, give or take. Much higher, and humans start being affected and you can run into altitude sickness and so on. Though of course, the local population would adapt. But even a city like Lhasa is only at 3700m. We're just not made to live above those altitudes. Already temperature and how well stuff grows is a big factor. You're for instance running into maximum height of the tree-line at those kinds of altitudes (the highest is in Bolivia at 5.200m).

Thanks!

Aren’t there thoughts that this is what Machu Picchu was for? More of a retreat for administration as you say. Would you have a Bailey, so to speak, with various farmers, weavers, healers, blacksmiths etc working to keep things running along?

In this case however it became basically a permanent residence, not a temporary retreat - so think Ravenna in the Western Empire, or post-1204 Nicaea.

 

[JBCrowson]

Thanks!

But just to note, this is not an originally mountain culture... rather, retreat to mountains was prompted by need for protection against sea raiders.

If it's simply a retreat then it need not sustain a significant civil population. Planning would then be more like 'how will we withstand a siege?' If sea raiders is the issue, then an isolated valley surrounded by mountains is also an option and allow stores to be built up as raiders gain a foothold on the coast. Sea raiders also means the raiders' supply chain (if they have any) will be stretched since they are unlikely to be able to bring much in the way of wagons / carts with them on ships or livestock to pull them. Humans pulling carts with supplies for an invading force over mountain passes will be very slow if not impossible, and therefore very vulnerable to attack by defenders who presumably would have some sort of cavalry available.
Sea raiders are unlikely to have the know-how / warm weather kit to cross high mountain ranges. There would be a risk of them triggering avalanches on themselves (or having no idea what an avalanche is when defenders trigger them). Any accessible passes can be guarded / defended successfully by small forces acclimatised to the altitude, while the attackers were suffering altitude sickness.

 

[Aldarion]

If it's simply a retreat then it need not sustain a significant civil population. Planning would then be more like 'how will we withstand a siege?' If sea raiders is the issue, then an isolated valley surrounded by mountains is also an option and allow stores to be built up as raiders gain a foothold on the coast. Sea raiders also means the raiders' supply chain (if they have any) will be stretched since they are unlikely to be able to bring much in the way of wagons / carts with them on ships or livestock to pull them. Humans pulling carts with supplies for an invading force over mountain passes will be very slow if not impossible, and therefore very vulnerable to attack by defenders who presumably would have some sort of cavalry available.
Sea raiders are unlikely to have the know-how / warm weather kit to cross high mountain ranges. There would be a risk of them triggering avalanches on themselves (or having no idea what an avalanche is when defenders trigger them). Any accessible passes can be guarded / defended successfully by small forces acclimatised to the altitude, while the attackers were suffering altitude sickness.

Few things:
1) These sea raiders had actually managed to conquer large parts of the Empire. So while the original intent may well have been a temporary retreat... well, said raiders had a) shown themselves adept at conquest, not just raiding, b) proven they are a permanent threat and c) are no longer a solely seaborne threat. Think a combination of Sea Peoples and Danelaw, except raiders / conquerors in question happen to be honest-to-Gods demons. So what this means is that right now, threat of an actual attempt-to-conquest siege is actually greater than that of "mere" raids, though raids are also a threat.
2) Mountains in question aren't that tall. Definitely not tall enough to have permanent snow and ice, or really any snow and ice outside the deep winter. Altitude sickness wouldn't be an issue either.

EDIT: Situation is actually similar to Tolkien's Minas Tirith... originally a retreat / fortress, it became a capital city by force of circumstance.

 

[skip.knox]

You might take a look around the Alps or the Pyrenees to help answer your question. The short version is, nobody builds a city on a mountain *top*. They build it on a river or lake, and they build it down in the valley. Put it on a trade route and the city flourishes. The only thing that goes up on the top of the mountain is the castle.

Also, how top is the top? I mean, the peak is what maybe a few hundred square feet? A few thousand? Nowhere near big enough for a city. So even the mountaintop town would spill down the sides. It still needs to be near lines of transport and communication, though, and most of the ordinary citizens will settle down there, not up there.

For another parameter check, look at the acropolises of Athens or Corinth. You can have a fairly extensive set of buildings and even inhabitants up on the rock, but the city itself is down below.

 

[Aldarion]

You might take a look around the Alps or the Pyrenees to help answer your question. The short version is, nobody builds a city on a mountain *top*. They build it on a river or lake, and they build it down in the valley. Put it on a trade route and the city flourishes. The only thing that goes up on the top of the mountain is the castle.

Also, how top is the top? I mean, the peak is what maybe a few hundred square feet? A few thousand? Nowhere near big enough for a city. So even the mountaintop town would spill down the sides. It still needs to be near lines of transport and communication, though, and most of the ordinary citizens will settle down there, not up there.

For another parameter check, look at the acropolises of Athens or Corinth. You can have a fairly extensive set of buildings and even inhabitants up on the rock, but the city itself is down below.

Trade routes are irrelevant in this scenario as there is basically no trade. The entire idea behind it is to secure existence of the administration and the population against more-or-less constant attacks and raids.

Also, I had changed it a bit from the original idea, so it is less of a mountain top and more of a hill top for the citadel and then the city goes down a series of plateaus:

 

[Prince of Spires]

if you want a population number, you can go 2 routes. If you look at historical figures, you can get an idea. Historically, Machu Picchu is estimated to have had about 1.000 inhabitants (at the high end). A place like Ollantaytambo (which doesn't sit on a mountaintop, but still at 2.700m elevation) had something like 15.000.

Another approach is to estimate how much land was available for agriculture, and take it from there. Google estimates a medieval farmer needed something like 1-2 ha to feed 1 person. Figure out how much room there is, and you can calculate what you can sustain.