Millions of Venetian Piles: where are they?



This is a tricky one, for the available information appears to be pretty confusing. As far as everyone knows our famous Venice was built on the water. That means they had to use wooden piles, and beaucoup of those. I remember watching The Italian Job movie where they were diving underwater in Venice. This is the image from that movie, where you can see those piles.


Wooden Piles
The Wiki-article about the city of Venice is as convoluted as it gets. Try to figure out when the city was founded, for example. As far as the infoon the wooden piles goes... well, here is all we get:
  • Those fleeing Barbarian invasions who found refuge on the sandy islands of Torcello, Iesolo, and Malamocco, in this coastal lagoon, learned to build by driving closely spaced piles consisting of the trunks of alder trees, a wood noted for its water resistance, into the mud and sand, until they reached a much harder layer of compressed clay. Building foundations rested on plates of Istrian limestone placed on top of the piles.
Now let us see what we can fish out from other sources.
Engineering Venice
Long ago the buildings were built by using long wooden piles (about 60’ long) driven deep into the ground. These piles go deep down into the soil, reaching past the weak silt and dirt to a portion of the ground that was hard clay which could hold the weight of the buildings placed on the piles above. The piles were also driven into the water which normally would have been a disaster as wood rots normally. The wood used in the construction of the piles was very water resistant but even so the wood should have rotted away eventually. However, several things happened which kept the wood intact for over 500 years. The first is that wood rots only when both air and water are present, so in the oxygen starved environment of the water underneath the buildings, the wood was protected until the second thing happened. The waters of the lagoon carried an extremely large amount of silt and soil and the wood was being blasted by this sediment for years. The wood absorbed the sediment and quickly petrified into basically stone at an accelerated pace. The wood used in the construction of the piles was also very water resistant such as oak or larch.

Siberian Larch (Larix Sibirica)
This is just a visual aid for a better understanding of what 2,000 miles separating the most eastern part of Siberia from Venice look like. Of course them Venetians chose to use the Siberian wood for their piles.


During the period V-XI centuries, the time of Venice’s Golden Age, and hence its rapid rise and growth in Construction required robust and long-lasting materials. The city opted for Siberian larch, Siberian larch traded by Scythians, ended up making the most of cores of the piles that the famous city on the water was built upon.
Venice was constructed between the fifth and ninth centuries and more than 400,000 larch piles were used to strengthen the foundations of many structures. In 1827, more than one thousand years later, some of the piles were examined. Conclusions about their strength stated that piles made of larch, on which the underwater part of the city was built, had become as hard as rock.
A 17th century book which explains in detail the construction procedure in Venice demonstrates the amount of wood required just for the stakes. According to this book, when the Santa Maria Della Salute church was built, 1,106,657 wooden stakes, each measuring 4 meters, were driven underwater. This process took two years and two months to be completed. On top of that, the wood had to be obtained from the forests of Slovenia, Croatia and Montenegro, and transported to Venice via water. Thus, one can imagine the scale of this undertaking.
Same Santa Maria Della Salute Church


The Piles - how many?
As we can see, our piles differ from 12 feet to 60 feet in lengths. It is also obvious that calculating the total number of piles in Venice does not appear to be attainable. A single Santa Maria Della Salute church required up to 1,106,657 (don't you just love the precision count?). They were allegedly driven underwater within two years and two months. That is 1,400 piles a day.

The way they drove piles in back in the day you can see in the image above. Here is what they use for the same purpose today.


As far as we can gather from various sources there were millions of piles used to build the city of Venice.

Where are the piles?
Naturally, if the water was to abandon the city of Venice, we would probably end up seeing at least a small portions of those millions of piles used, right? Well, in November of 2012 the water did temporarily abandon the city of Venice. Here is what it looked like when it happened.









What about the past?
1956 Clean Up



KD: To be honest, I thought them Venetian canals were much deeper. I also was under the false impression that the entire city was built on those wooden piles. May be they are hiding the millions of piles somewhere else, but I find the available photographs of the city of Venice free of water to be somewhat suspicious.
  • Doesn't it look like the sea levels went up, and flooded a pre-existing city to the point where it was still possible to live there?
  • So... how many piles did they use?


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Went looking for photo's on startpage using the string restoring a venetian house. Before I got to the images I scanned the search results;
Why is this organisation, headquartered in London?
UNESCO assistant director-general for culture Francesco Bandarin recently wrote to Italian minister of the environment Corrado Clini to express "longstanding concern" over the risk that cruise ships pose to Venice. In a statement released Monday, UNESCO accused the ships of causing tides that erode the foundations of buildings, create pollution, and dwarf the city's monuments. The Venitian Lagoon and the Basin of San Marco are both World Heritage sites, though maritime traffic in the area is high — according to the Daily Mail, 629 cruise ships passed through the City of Bridges last year. Venice mayor Giorgio Orsoni has already spoken to the port authority about the possibility of moving cruise ship terminals to the mainland.

Foundations gets a mention but not piling.

Someone is telling porkies about the piling.
Timber Usage in Venice
Timber was a popular commodity in Renaissance Venice because it was used for shipbuilding, house carpentry, and making oak and pine piles, or tolpi, which were staked vertically into the ground to create a solid foundation for building heavy structures.
Wood usage was especially widespread in Venice because the nobility owned much of the forests of the Terraferma, or mainland, and realized its economic potential.1 This reliance on the Terraferma was not a new concept for Venetians: these island-dwellers had to reap the bulk of their agricultural commodities and building materials, like wood and stone, from the mainland.

I reckon it's nowhere near as old as we are told. Just a feeling of mine which appeared whilst looking at these two site.


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copying a post from a couple of months ago:

Was the city of Venice created in the 17th Century?
Venice is known for it's hundreds of beautiful canals. Unfortunately the city has been deteriorating as long as people have documented the state of the city, so it's surprising to see historians claim a supposed history of more than 1000 years.

I found an old map from the late 16th, early 17th Century, which does not show Venetia.

Instead, it shows the supposedly old, antique, city of "Altinum", which, according to Wikipedia, Altinum:
is the name of an ancient coastal town of the Veneti 15 km SE of the modern Treviso, northern Italy, on the edge of the lagoons. Located on the eastern coast of that nation, at the mouth of the river Silis, it was first destroyed by Attila in 452 and gradually abandoned by its inhabitants, who sought refuge in the islands of the lagoon, such as Torcello and Burano, in the area where later Venice would be built.
Altinum was abandoned by its citizens and then sank into the lagoon.
According to archaeologists, Venice's ancestor was surrounded by rivers and canals, including one large canal that ran through the center of the city and connected it with the lagoon.
A digital reconstruction of the area shows that the city stood two to three meters above what was then the sea level. The structure of Altinum was complex and perfectly suited to the particular demands of the swampy environment. Researchers say that it looks like the Romans knew how best to build on this harsh, swampy landscape -- long before they began the construction of Venice in the middle of a lagoon. (source)
The official story is that Altinum was destroyed in the 7th Century AD
But as waves of barbarians invaded, Altinum was a ripe target and, finally, in the 7th century AD, a Lombard invasion pushed the city's remaining residents onto the surrounding islands of the Venice lagoon. (source)
Is it possible that the modern Venetia is not only a product of that catastrophe leading to the sinking of Altinum, but basically a re-incarnation of Altinum? Is it possible that Altinum didn't sink in late antiquity, but only 350 years ago?

Alternative szenario: Here is evidence of the invented 1000-years that Fomenko speaks about, and when the city of Altinum sank somewhere between 1600 and 1700 (in the 17th Century, not the 7th), people were able to save parts of the city, now submerged underwater.
Voila, Venice was (re-)born.

The mentioned 17th Century map clearly shows Venice to not exist, and Altinum to exist. By the way, it also shows Pompeii alive and kicking.
What archeologists are digging out at the historical site of Altinum isn't the entirety of Altinum - it's a small part of a way larger city, most of it now submerged under water or rebuilt into modern Venice.

Before Altinum/Venice god flooded in the 17th Century, maybe with the same event that destroyed Pompeii and Herculaneum, it was a big city full of water canals, but built on top of the land. The canals did not fill every street, they were strategically built to transport stuff out of the city:

(The orange part is the canal)

This was how the modern area of Venice was built as well, but all streets got flooded with water, so they re-designed the city to work without streets.
You can see the original big "true canal" run through the inner city:

which originally was basically water-free.
The name of this canal is "Canal Grande", and it follows the natural flow of the original river (called Brenta) that predates the canal. Which means, the canal is not artificial. I suggest: The city was built around this river, originally.

In the 20th century some people thought Venice was some kind of magical city, resting entirely on wooden constructs, like this painting suggests:

But when, in 1996, the theatre „La Fenice“ burned down completely, people were for the first time able to look at the underlying structure.
Turns out, the buldings rest entirely on stone walls. Only the reinassance style facades rest on wooden stakes, suggesting a rebuilding effort where the facades had been renovated in line with the new reality that the houses were now basically surrounded by water.

Interestingly the front facades are not completely connected to the houses, but are a bit loose, which means that the city design is earthquake resistant. The front sides are built on top of water-proof limestone (Istrian Stone) to not let the water slip through the facades. This suggest the facades were built later, as a way to protect the original houses from the new water level.

All in all I think Venice as we know it was recreated from Altinum around 350 years ago, with an enourmous building effort to create waterproof and stable house-facades, protecting parts of the original city.

Interestingly, historians do not know how and by whom Venice was created, the origins are entirely in the dark. I suggest that Venetians simply made the best out of it when their city of Altinum was destroyed in the cataclysm of the 17th Century that also destroyed Pompeii and Herculaneum, and many other parts of the world. Parts of the city of Altinum survived, but were now surrounded by a lagoon of water, so in an effort to save a significant part of the city, front facades were built. What they could not save, they demolished.

When the Vatican church created the 1000-year history hoax, the history of Altinum was put back 1000 years into the past, with historians saying it was abandoned in the 7th Century. Instead I suggest it was in fact only abandoned in the 17th Century, and it wasn't run over by attackers, but it was simply submerged in a giant catastrophe. The partially submerged parts that survived became modern Venice.


Active member
Most likely just a flooded city. As a result of flooding, city streets became canals.

Those fleeing Barbarian invasions who found refuge on the sandy islands of Torcello, Iesolo, and Malamocco, in this coastal lagoon, learned to build by driving closely spaced piles consisting of the trunks of alder trees, a wood noted for its water resistance, into the mud and sand, until they reached a much harder layer of compressed clay. Building foundations rested on plates of Istrian limestone placed on top of the piles.
Even in a straight line less than four kilometers from the mainland, this is not counting the heaps of islands.
Very dubious defense against barbarians.

Historians, as usual, had to come up with a realistic version of the emergence of a city on the water.
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wild heretic

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Yeah, I looked into this a little bit last year after I remember New Earth mentioning that Venice was really flooded and a normal above ground city. The two pieces of damning evidence is one of those photos Korben posted which show cobbled streets (aka the bottom of the canal), and very old mappa mundis which show an entire large island as the province of Venice, not a "lagoon-ed" city.

I have a similar photo on my computer somewhere. I'll dig it up. Here it is.

copying a post from a couple of months ago:

Was the city of Venice created in the 17th Century?
Venice is known for it's hundreds of beautiful canals. Unfortunately the city has been deteriorating as long as people have documented the state of the city, so it's surprising to see historians claim a supposed history of more than 1000 years.
Good find.

No Venice in the 16th century eh? Mmmmm. There in the 1200 to 1400s as an island, then wiped and nothing, then rebuilt so it seems.
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Active member
Here is the birds eye view from Jacobo De Barbari, dated 1500.

high resolution src // file has > 10 MB

1493 Hartmann Schedel


much more city maps:
1552 Sebastian Munster
1572 Georg Braun
city maps
Houses on stilts
Venice was long believed to stand on a forest of tree trunks. However, this is only partly true: the city stands on the sandy and muddy ground of the numerous islands.

The foundations on which the walls of the palazzi and churches were built are usually four parallel rows of walls arranged perpendicularly to the canal, built up to 80 centimetres deep into the ground.

Only the facades on the canal side actually rest on tree trunks: To prevent the walls from slipping along the banks, three metre long oak, alder or poplar poles were rammed into the ground at half a metre intervals. The gaps were then filled with clay and silt to form a solid foundation.

In order to prevent the wood from rotting, however, this block of wood and clay had to be completely under water. The buildings themselves are mostly made of wood, limestone and clay bricks. This special construction method is so stable that it has survived for centuries.

Nevertheless, the buildings are threatened by water. Venice threatens to sink into the lagoon. Because the sandy and muddy subsoil of the islands on which the foundations stand gives way under the enormous weight of the buildings. The city sinks by a few millimeters every year - in the past hundred years by a total of 23 centimeters. In the meantime, many ground floors are no longer habitable.

Translated with

Building land and structure in Venice once and now Swiss lecture from 1960
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Do we have any structural engineers on the forum?
To me, the wood piling idea seems like a poor man's patch and fix idea. How do you make them level for a foundation?
Wouldn't they constantly settle?
Venice must have originally been constructed when sea levels were lower.
Why would the Venice OTB lie about the foundations?



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The first is that wood rots only when both air and water are present, so in the oxygen starved environment of the water underneath the buildings, the wood was protected until the second thing happened. The waters of the lagoon carried an extremely large amount of silt and soil and the wood was being blasted by this sediment for years. The wood absorbed the sediment and quickly petrified into basically stone at an accelerated pace.
The first part is ridiculous and the second part is convenient.



Link to PDF


Well-known member
Doing a startpage search for the string piling in Venice.
Found these;

The foundations of Venice’s palaces follow the same system of indirect foundation: think of a swamp ; you have to solidify the zone and then put wooden pointed knotty and short poles until you find a hard and compact layer of clay in the soil, called caranto which is located at a dozen meters below the surface soil layer of the lagoon.
The piling of the poles is carried out according to multiple alignment, along the strip where the perimeter walls will be built, supporting most of the building.
And where did the Venetians get these poles? It was necessary to deforest many areas of Cadore and Istria.
Venetians chose trunks of firs, oaks and larches that arrived through the rivers in Venice.

So that's the Siberia story shot down again.

As for the poles turning to stone courtesy of the sea or the mineral content of this caranto mud which somehow changes wood to stone in the absence of oxygen well the muddy ones in this picture look 'woody' to me and they appear to be joined to the brand new ones by a wooden beam. How is anyone's guess.

From here; How was Venice built? | So how do you build a city in the swamp?
Similar story really.
A few meters down under the bottom there is a layer of hard clay, the so-called Caranto. This is very fine-grained sediment that has undergone a process of over-consolidation in a subaerial environment. Kind of technical but it basically hard mud, and it withstands weight better than soft mud. So if you reach the Caranto it is obvious that the resistance is greater than just piling down into the upper layer.

Millions of piles knocked in by hand, roger that!

Seriously, How was Venice built? The Venice lagoon is all mud. There is no rock to construct on, so to build stone houses that weigh hundreds of tons you have to follow an ingenious and thorough strategy. And the strategy is to drive long pointed poles of wood; oak, larch or pine, straight down into the bottom and then construct houses on top. This is a very ancient technique. The method existed even as long ago as in the days of the Roman empire. The Venetians just improved and developed it.
The first settlers didn’t use this technique because their houses were much more basic. They were made from wood, reed and clay and they where lightweight. They just constructed on the existing islands, on the sand. As Venice increased its importance, they needed more space. So they had to build where there was no land, directly on the water. And later on the palaces became heavier and the foundation had to be stronger. In fact, most of the underlying woodpile ground, that nowadays covers most of Venice is from the 15th and 16th century. Before that piling wasn’t all that predominant.

The hard floor?
A few meters down under the bottom there is a layer of hard clay, the so-called Caranto. This is very fine-grained sediment that has undergone a process of over-consolidation in a subaerial environment. Kind of technical but it basically hard mud, and it withstands weight better than soft mud. So if you reach the Caranto it is obvious that the resistance is greater than just piling down into the upper layer.
But here we need to dismantle a myth.
It is not like we have a hard, flat bottom of stone-like clay on which the woodpiles stand. The caranto is found at various levels. It can be as shallow as two meters and as deep as more than ten. And it’s not stone hard. It’s more like a very dense rubber like material that holds the pile better than normal clay. The construction engineer of the middle ages probably started with the piles and as work progressed he put more or less of them in a certain way. He knew from the resistance if the clay was hard or soft and he adjusted the numbers and placement accordingly. Normal precaution told him to put more piles under the outer walls where most of the pressure is. Because there was no way to determine the structure of the material 5 meters down into the seabed, in advance. And this is how Venice was built: Without too much technology but with a lot of craftsmanship.

Ever tried knocking a nail into hard rubber?
And yet two men hand piling could knock a pile say 6 inches wide down through many feet (sorry don't do metres). How did they get thirty feet off of the mud to start knocking it in and how the hell was it held upright so they could knock it in?
Answers on a postcard.

But it gets better.

Continuing with the building technique… On top of the piles there are two horizontal layers of thick, cross-plied wood planking and on top of that the bricks and stones. The part of the foundation standing against the water of the canal is made of Istrian stone, a dense type of impermeable limestone from the peninsula of Istria on the Croatian side, opposite of Venice.

Presumably the flat planks are not in the rubber mud stuff but in ordinary aerobic mud so why don't they rot out?
Anyone heard of marine worms?
I'm not up on geology but isn't limestone and all sedimentary rock porous to some degree?

So why doesn’t the wood piles rot?
Because they’re stuck into the mud. And inside the sludge, the air doesn’t have access. The wood has no contact with oxygen and the microorganisms doing the decomposition just can’t work. Instead, the minerals from the humidity make the wood harden. When the belltower in Saint Marks square collapsed in 1902, the piles underneath where still in more or less perfect conditions… after a thousand years. And they had turned into stone…

So 'the humidity' (saturated mud cannot be humid) can transfer minerals from the mud to the wood, I have no idea how, which makes the wood sodden but leaves it free of oxygen and therefore rot or worm attack whilst the magic of time turns it into stone.
Assuming that were possible how did they remove the stoned wood piles secured in the hard rubber mud in that photo above so completely they were able to knock some new ones in?

How was the caranto mud layer under Venice discovered?


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Maybe the real question is why did they go to all that effort to make a wood piling "Old World" swamp city?
Is the historical record valid?

barbari 1.jpeg


Venice in the Middle Ages
According to tradition Venice was founded in 421 AD. At that time a Celtic people called the Veneti lived along the coast of what is now Northeast Italy. Since 49 BC they had been Roman citizens. However, in 453 Attila the Hun invaded Italy. In terror, some Veneti fled to islands in the lagoon and built a village there. They soon formed a loose federation. Then in 568 AD a people called the Lombards invaded the mainland and many Veneti fled to the islands swelling the population.

At first Venice was controlled by the Byzantine Empire (the Eastern half of the Roman Empire, which survived the fall of Rome). However, in 726 the Venetians partly gained their independence and elected Orso Ipato as doge (their word for Duke).

In 810 the Franks tried but failed to conquer the Venetians. Meanwhile, Venice flourished as a trading center and ships sailed to and from its ports. Its population grew steadily. In 828 the body of St Mark was smuggled from Egypt to Venice. St Mark then became the patron saint of the city.

In the Middle Ages Venice continued to flourish as a port and trading center. Meanwhile, in 1199 a fourth crusade was proposed. The Venetians agreed to build a fleet of ships to ferry the Crusaders. However when the Crusader army assembled they were unable to pay for the ships. So the Venetians persuaded them to join an expedition to raid Constantinople. Venetians and Crusaders captured the city in 1204 and they looted it. Venice was also involved in other wars at that time. The Italian city of Genoa was a powerful rival to Venice and during the 13th and 14th centuries the Genoese and Venetians fought 5 wars.

Furthermore in 1348 the Black Death devastated the population of Venice. Therefore in 1403 Venice introduced quarantine. Ships arriving from infected areas had to stop at an island called Lazaretto and the passengers had to wait for 40 days before they were permitted to enter the city.

In the 15th century Venice faced a new threat - the Turks. In 1453 they captured Constantinople and afterward they advanced into Southeast Europe. In 1489 Venice came to rule Cyprus. However, in 1571 the Turks conquered the island.

Furthermore in 1508 several European countries formed the League of Cambrai and went to war against Venice. However, after 8 years of war, the map was largely unchanged.

BArbari 2.jpeg

Now, theres an old story that Roman parents would warn their kids that if they didn't behave well then Hannibal would come for them in their sleep.
I find that Attila the Hun is a convenient and plentiful excuse for many things that happened in "history." Like, say:

• My kids burned down the barn. --Atilla.
• Lets build a star city nearby at Palmova. --Atilla.
• Lets build a city on a swamp, no one will invade by ship! --Atilla.

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That group of piles above, the black n white photo, is apparently the underpinnings of an unnamed palazzo The foundations of Venetian palazzos - Venice Wiki, la guida collaborativa di Venezia
If the layer of caranto is too deep and the posts do not arrive, in whole or in part, to conficcarvisi, the sub-foundation is made by compaction. In this case the poles are planted on the entire surface above the joists of the building, before closing the loop with a dense palisade and then proceeding inside with a spiral design towards the center of the area.

So mud that is soft and aerobic is filled with timber because the hard rubber mud is beyond reach so what exactly supports the weight of the building?

Above the heads of the poles two crossed layers are bound together by larch planks. Above this special raft is high the real foundation, formed by a plinth to the wall, ie in the socket with the slightly sloping walls, at fairly regular layers of stone blocks of Istrian. Above the stone wall they are placed columns, or the walls of the building.

The 'special raft' in aerobic mud!

The foundations of such buildings are now made of strong poles of oak, that eternally last under water for respect of the slippery fund and not firm point of the swamp. These rents for strength in the ground, then stopped with big beams, and full between the one and the other of wrecks of stone, they succeed for the coagulation and taking their as bases so stable, and firm, that sustain every big and firm wall.
The sones are had by the Brenta, and from the Beach, but the sweet ones are best.
Lumber are brought us in abundance for the Rivers from the Mountains of the Cadore and near Treviso; the alive stones proceed from Rovigo and from Brioni; and the iron from the Lombardy.
This way it became magnificent this Metropolis to the peer of ogn'altra to the World, from what they are admired with amazement Monasteries, Churches, Towers and many other of sum massive structure, as well as immovable, sustained by ruinous relics of lands, desolate or from the insult of the times, or from the ferocity of the Barbarians.
To the Signor Pubblico Foreman Antonio Mantoan, because succeeds to our easier duty this difficle it conceives, we made invocation.

A translation to be sure but even so what is this Dutchman Jan Grevembroch on about. I realise the page appears to be a machine translation from the Italian but nevertheless.


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My mind is blown simply at the number of trees that had to have been cut down. Entire forests would have been destroyed, and wouldn't the countries that owned the forests be pissed off that their trees--which they needed for their own building projects--were going to some foreign country to put a city in a swamp? Why not just build the city on dry ground somewhere else? And why build exactly the same kind of city that could be found all over the world, as opposed to something that would be better suited to a watery, swampy environment? Maybe something like this: A City on Stilts Inly Lake, Myanmar/Burma Part 2 I just don't think that massive concrete-and-stone buildings, weighing thousands of tons, are the right sort of architecture to put on wooden stilts. As usual, we are given a historical narrative that makes no sense, but millions of people keep on believing it, anyway.


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I live in a part of the Netherlands where the top layer consists mainly of clay and to a small amount left over peat bogs. Some centuries ago this was also marshy / swampy terrain just like Venice before our ancestors started draining the area.

Not a very stable underground for building heavy stones houses / churches / official buildings so for that reason in the old days large buildings were kept as light as possible with mainly wood before stone buildings become more popular / practical.

When building houses around my area reinforced concrete bars are driven in the ground for a depth of on average 20 meters / 65,6 feet before reaching a sand layer.

In Amsterdam for example some of the old monumental buildings you're seeing are resting on hundreds or thousands of wooden poles each.

Palace on the Dam Square (construction 1648-1665) is resting on more than 10.000 wooden poles.

The average depth unto the sturdy sandy layer in Amsterdam is about 13 meters / 42,7 feet.

All this wood came and still comes from Scandinavia / Baltic Region. In the medieval area courtesy of connections / trade within the Hanseatic League.

Like mentioned in the thread just like other cities / area's we're having troubles with the rotting of the wooden pole foundations because of the ground water levels.

It's costing a lot of money and effort to stabilise these foundations underneath old buildings now and in the future.

So these conditions are the same as Venice, a major difference that occurred in my mind while reading this thread is the fact that in the 15th century maps mentioned before, Venice already was a grand engineered city with marvelous buildings resting on countless of these wooden poles (well maybe not all which could be indeed the case).

To give a frame of reference :

In the Netherlands it was only between 1500 - 1600 that we've found out that it was better to drive wooden poles all the way to a solid ground layer (mostly sand) instead of driving poles in the clay / peat in a higher density in a framework but not reaching a solid ground layer.

In a clay soil when conditions like ground water level don't change the poles "stick" to the clay thus giving a sort of "solid" foundation so that's why in the beginning they saw no need for driving poles all the way to a solid layer.

And of course this would take extra effort.

But ground water levels do change and there were problems with the "drifting / deviating" of the poles thus causing tears in brickwork.

The latter was the foundation technique used for heavier buildings in the 12th - 15th century around here if funds were available. Even then this foundation technique wasn't common practice.

So from the 16th century we sort of started to overcome these problems and (re)-invent building foundation techniques that would lead to an urbanized area, the expansion of Amsterdam and other Dutch cities (16th-18th century) rivaling Venice.

But Venice had all this covered from the 8th / 9th century ? I'm just going to blame the Dark Ages and such that we've been an barbaric ignorant region for so long :)