Building a city on top of, alongside and inside a coastal cliff

Question

The capital of the society my story revolves around is built on top of a cliff, similar to the White Cliffs of Dover (pictured below for reference). For story reasons, they settled in this location after fleeing another continent and had few options due to less than friendly neighbors.

In the present, the city has expanded outwards into the mainland. They use a Gothic style of architecture, meaning a lot of stone is used in construction. In order to better utilize the ocean and maintain a port, a network of wooden scaffolds have been built into the cliff face. Small rooms are carved into the stone at certain intervals, to anchor the scaffolds, act as places for shops, storage and a stable refuge if the scaffolding begins to collapse.

My question boils down to this: is the city's location practical? Would the stone in the cliff be able to support the weight of the city and would the scaffolding actually allow the city to act as an effective port? Is there anything else I might be missing?

I haven't seen an example of a city like this (real or fictional), so any examples for reference would be appreciated.

Answer 1

Allow me to introduce you to Santorini

• Santorini is a Greek Island in the Aegean Sea.
• On a side note it is posited as possible the location of Atlantis.
• The island used to not have a giant hole in the middle of it and was more round. The center is a volcanic caldera.

The explosion of the volcano left the inside of the eastern island looking likes this...

There are also caves carved directly into the face of the caldera but I am having trouble finding pictures of them on the googles...

To answer your questions.

1. Is it practical? Well, practicality is situationally dependent. So you can make it practical without a doubt. Better put, it is certainly plausible

2. As long as you allow for cranes and other items to hoist things up the wall, it could function as a port (though it will never be as efficient as more natural ports).

A couple ideas on plausibility

• Geographic location. Sometimes you need a port as a way point when the full distance is too great. In that situation you work with what options you have, if in your scenario the option is an island with cliffs...

• Defensible. If the threat of attack from the sea is a constant problem, be it another nation-state, pirates, vikings...being atop a cliff makes attacking the town a whole lot harder.

• Point of interest. Not sure what your setting is but the island could have religious significance, importance to a king/leader, or be a tourist destination.

Answer 2

Lots of places built into the sides of cliffs in history. Transporting people and materials would have been difficult and they used surrounding plains for their agriculture, forests for wood, animal enclosures etc,. rather than being self sufficient in their cliffs.

Ireland has around 100km of (now buried under peat) stone walls which were used as animal enclosures atop a cliff. So there is nothing that stops the top being used if you can defend it.

All that is necessary for a port is deep water close in and a sheltered harbour, so given that then yes, you could have a port.

Here's a link with other real life examples Click me

Answer 3

(NOTE: I started writing this answer before @amflare posted theirs, and before @AlexP posted his comment.)

The existing answers do a good job of demonstrating that you can build a city on the side of a cliff, so let's look at whether you should.

The main problem you'll have is that cliffs erode. They will, over time, retreat inwards, eating away at your caves and creating a gap between the scaffolding and the cliff face. It's a very gradual process, and depending on the geological makeup of the cliffs, it should be gradual enough for your townsfolk to be able to keep pace with it (moving the scaffolding, digging the caves deeper, and so on). I'd like to note that the cliffs in your picture are made of limestone, which erodes very quickly.

Cliff erosion will probably be more of a danger to the stuff on top of the cliff. There are numerous examples (@AlexP linked one of them in his comment) of cliffside houses that have had to be abandoned because the cliffs have eroded their way right up to the back door and the house is now about to crumble into the ocean.

In your case, if a cliffside house were to collapse, the falling debris would also wipe out anything on the cliff face below it, so it's probably not a good idea to build too close to the edge - or if you do, demolish the house as thoroughly as possible before the cliff edge reaches it, otherwise you're in trouble.

You'll also want some kind of coastal defences, because I imagine a city built on the side of a cliff is going to be wide open to naval bombardment. Fortunately, you can do all kinds of crazy stuff depending on your story's tech level, from Archimedes' solar mirror death ray thing to giant cannons hidden in alcoves inside the cliff face.

As for the positives: it would make a great port town; it'd be very easy to defend from land-based attacks, as enemies can only come from one direction; and you'd have one hell of a nice view.

Answer 4

I don't know much about the White Cliffs of Dover, but I can offer some personal observations of the coastline around San Francisco.

The cliffs themselves: When I see cliffs with nice, clean, well-defined edges, I immediately assume the cliffs are unstable. Oceans typically come with lots of strong winds and lots of sand/dust/grit in the air. These phenomonon act as natural sandblasters to the local geology, turning sharp edges into smooth, worn slopes. If a cliff edge is sharp, that says to me it has not been exposed to the ocean air long enough to get worn down. That says to me that the leading edges of the cliffs collapse so frequently, wind erosion don’t have time to have a significant effect on the edges before they fall and are replaced with new edges.

The cliffs in your photo do not have a bunch of structures at their edges. This is probably because (according to weather.com) the cliffs are eroding at a rate of 8 to 12 inches per year.

Ships docking at the port: Your ships will have a heck of a time docking at your port. Those unstable cliffs have been shedding boulders and who knows what else into the ocean for centuries. This means the ocean leading up to the cliffs have been changing a lot. There probably won’t be a lot of well-known, safe approaches to the land. Ship captains will have to stay far back from the cliffs. There won’t be many soft beaches for the rowboats to approach. Docks will have to be constantly moved around to accomidate the changing landscape. Remains of abandoned docks will litter the ocean around the beaches, causing more navigation hazards to ships. Your city is in for a LOT of upkeep work.

The city atop the cliffs: People get upset when their houses fall into the ocean. For example, look at the Esplanade in Pacifica, California. In the 1960s, apartments were built a few hundred feet back from the cliff edge. There was a small strip of land, a community swimming pool, and a road in between the cliff edge and the apartments.

In 2010, the apartments were condemned by the city. One of the back porches attached to the complex fell into the ocean. The pool and road were long gone. Many of the apartment’s residents refused to move out. They sued the city in an attempt to remain in their apartments. They claimed the city had a responsibility to protect the apartments by reinforcing the cliffs. The city had been attempting to reinforce the cliffs for years, moving giant boulders down to the narrow beach below and piling them up against the cliff edge. Boulders used in this manner are called riprap.

Spoiler alert: Riprap doesn’t work. The water seeped through the gaps between boulders and continued eroding the cliff.

The city tore down two of the apartment complexes. We’ll see what happens to the rest of them.

In summary, your city can try anything they like, but the ocean will win this fight. The disaster will be slow-moving and a lot of people will refuse to believe it is happening. In the end, whoever owns the infrastructure immediately around the cliffs will likely experience total financial ruin.

Bibliography:

White Cliffs of Dover erosion rates: https://weather.com/science/environment/news/england-dover-cliffs-erosion

California coastal town of Pacifica dealing with erosion: http://www.cbsnews.com/news/sinkhole-california-pacifica-coastal-erosion/

Pacifica apartments almost falling into the ocean: http://kron4.com/2016/03/07/pacifica-apartments-at-risk-of-falling-off-cliff-set-for-demolition/

More on Pacifica, here are a series of photos from 1972 to 2016 showing the erosion progress: http://www.sfchronicle.com/bayarea/article/Pacifica-cliff-disaster-Photos-1972-to-today-6801897.php

The fate of the Ocean Shore Railroad, built on the cliffs in the same general area as the aforementioned Pacifica apartments: http://www.cityofpacifica.org/about/history/ocean_shore.asp

And the fate of Devil’s Slide (a former section of California Highway 1), about 10 miles south of the apartments: https://en.wikipedia.org/wiki/Devil%27s_Slide_(California)

Answer 5

Is the city's location practical?

Well, you first need to ask "Why is it a cliff?" Keep in mind that cliffs are sheer for a reason and tend to endure a fair amount of abuse from sea and storms. So how long do you want the city to be there?

Would the stone in the cliff be able to support the weight of the city

Yeeeeeeeeessssss. Technically (unless it was really soft stone). But as mentioned above, the structural support of the stone won't be be main issue here. It'll stand for the same amount of time no matter what. The obvious exception being if you riddle it with so many holes that it clearly won't stand. But assuming you are mindful, it won't be an issue.

Would the scaffolding actually allow the city to act as an effective port?

The scaffolding won't work. I'll refer you to the comment above about the amount of abuse applied to the cliff face.

Is there anything else I might be missing?

Not that I can think of, but I do have an idea for you. IDK what the timeline is for your story, but what you could do to mitigate many of the issues is have the city retreat back into the cliff face. Each generation tunnels back a little further. So as the cliff erodes, the city just moves further back. Obviously since the humans are doing part of the work of "eroding" this section of the cliff will erode quicker and slowly create an inlet in the landscape, which could lead to some interesting opportunities for city layout.

Answer 6

For a port you need a bay or other protected body of water. Or else ships caught in port by a storm will be smashed against the cliff and into docks and buildings.

Many river, lake and sea ports were and are multi leveled. The docks are at the level of the water and the buildings are at various levels on gentle slopes, sheer cliffs, natural and artificial terraces, etc. etc.

In Naples, for example, the buildings climb up hillsides, though not as steep as you would like.

https://www.google.com/search?q=sea+port&espv=2&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjDwYfoh8DTAhUn4IMKHeJ7DnsQ_AUIBygC&biw=1280&bih=894#tbm=isch&q=italian+seaports&imgrc=yabWQsZjGWzB6M:[1]

Istambul. Again,not a steep as you asked for.

https://www.google.com/search?q=istambul&espv=2&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjSx4zYicDTAhUC5CYKHZq4CCQQ_AUICCgD&biw=1280&bih=894#imgrc=A1lLVfAvIAuZKM:[1]

Santorini looks closer to what you asked for.

https://www.google.com/search?q=santorini&espv=2&source=lnms&tbm=isch&sa=X&ved=0ahUKEwitoKiTisDTAhXG4yYKHXXkCXoQ_AUIBygC&biw=1280&bih=894[2]

Rio has mountains, but most of the buildings are in the flatlands:

https://www.google.com/search?q=rio+de+janeiro&espv=2&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjRz8DcisDTAhXLwiYKHeaUAH0Q_AUICCgD&biw=1280&bih=894[3]

Dover has buildings at sea level and other on top of the cliffs.

https://www.google.com/search?q=Dover,+Kent&source=lnms&tbm=isch&sa=X&ved=0ahUKEwi8mMHijMDTAhXERiYKHUOGB1wQ_AUICigD&biw=1280&bih=894[1]

And "seaports with cliffs" yields some interesting images.

https://www.google.com/search?q=seaports+with+cliffs&espv=2&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjTpu6SjMDTAhXCWSYKHXUdCq4Q_AUIBigB&biw=1280&bih=894#imgrc=_[2]

Answer 7

There could be a reason you haven't heard about cities on cliffs. The reason being those cities no longer exist. One of the examples is Trzęsacz (welcome to Polish 101).

It doesn't take long to notice that sea or ocean have an impact on a shoreline. Also having a port (and not a defensive castle) would require additional work for loading and unloading ships which would occupy the piers for longer time. I'm not a marine expert but I think that such coast would have been exposed to much harder, stronger waves than normal ports which are usually located in bays.

So the city could get a finite amount of goods in a time window set by tides. And people would notice very quickly to go into the mainland and find other terrains more suitable than try to live on the cliff.

Answer 8

It is possible that the cliffs formed at an earlier point in history, then other geological changes had the cliff become a bay. You'd still worry over erosion, but not at the rate you see on a typical cliff shoreline.

Make it a nice, hard stone, with the cliff forming from some type of rapid-onset natural event (earthquake, volcano, meteor impact) and you could see a city on a cliff for thousands of years. But, yes, parts of that city would be falling off every now and then, and you'd see a lot of civil engineering around preventing or responding to erosion.

The scaffolding is unlikely to work; stairways and such carved into the cliff sides would be more feasible.

Answer 9

I'm surprised no one else has said about this...but what about cliffs that don't go into the water? I know you're showing Dover in your picture but cliffs don't have to be by the sea, it could have once been by the sea (so you get the carved out limestone and everything) but the water level could fall and leave a cliff in the middle of land but maybe with a river still to connect it to the sea.

Obviously this helps avoid the erosion problem where your city ends up falling into the sea.

You could carve tunnels into the stone to get you down to the bottom like in Nottingham. This would give you a lot more protection against the elements as you go down to the docks.

Answer 10

If you don't insist on a seaport, but the cliffs represent a choke point on a trade route, you could do worse than using Petra, Jordan as an example of what your city might look like.

Answer 11

It's a bit different as it is more a town for leisure but I thought it might be worth mentionning Sorrento in Italy near Naples at least for possible inspiration from its stairways and architecture.

As for the risks due to the location : yes, but scaffoldings or parts of the city falling in the ocean every now and then it can be a prettry nice (maybe not the perfetct word) allegory of a people ouf outcasts litterally living on the edge, struggling to develop their city falling apart almost as fast at it's being built, people living over the void wondering whose house wil be the next to sink.