How long does stuff last after death/collapse of an empire?

[Eric Tolle]

On Earth, even with shoddy human construction, the answer is "a bloody long time". I'm pretty sure that if we vanished right now, many of the buildings in our cities would be standing in ten thousand years, perhaps much longer.

Actually, due to the different construction techniques we use now, very few, if any of our structures will be standing for any appreciable length of time. Without constant maintenence, buildings will collapse within decades, bringging other buildings down. After a few centuries, the only thing to indicate there was a major city to the casual observer would be a profusion of non-native plants and animals.

Climate will make a large difference of course- the ruins and rubble of desert cities like Las Vegas will be visible for much longer than temperate or coastal cities. But in the main, the major traces of mankind's presence would be lines of differing vegetation following major roadways and in cities.

Some references:
Post-human London
Chicago...Without Us

After a hundred thousand years, something would need to be somehow protected from the elements and made of a hard rock to be easily recognizable as a building, that's for sure. The problem is, of course, that we don't have anything that old, per se, apart from debris of our ancestors.

It's arguable that the pyramids and some of the other Egyption structures would still be standing, though even there the elements will have polished it down quite a bit.

What will really survive will be protected areas, like caverns and sunken areas, and the equivalent of our middens: landfills will be recognizable as artificial for hundreds of thousands of years. Likewise, even after they are filled in, mines and artificial caverns will be recognizable as artificial from the inclusions of foreign material in the rock layers.

And oh yes, there's also vacuum. the luner modules will probably outlast anything on Earth.

 

[Silverblade The Ench]

Ok, long post, sorry
I@m not an archeaologist buit I love history etc.

1. There was a recent program on channel4 here in UK, that showed within 100 years most modern buildings and bridges would all be gone, they are crap for durability wthout constant attention, Victorian solid stone structures may endure for hundreds of years.
   the Pyramids woudl last for maybe 10,000 years, they are SOLID. Stonehenge has been around for 4,000 years and runes are still barely visible on it's granite. Please note that Humans do more damage to structures than most things, by stealing rock for other buildings, and chipping bits off and graffiti. Acid rain from pollutiuon, vulcanism and earthquakes etc all cause massive damage.
2. Iron corrodes very fast, even gold can corrode as it's often impure but gold object should last for many thousands of years, pure gold and platinum could lasts until physically damaged. Many gemstones are also "Immortal" though prone to shattering if struck. granite walls etc in Aberdeen over 100 years old still have sharp edges, granite's incredibly durable but requires diamond or magic ot cut it effciently. Stainless steel could endure for thousands of years, but it's not a technology you'd expect to find much, though, IMHO dwarves after millenia of crafting should have it, in my homebrew world, "dwarven steel" is stainless steel.
3. Magic and Otherworldliness. magic could make things last for who knows how long, plus, other world's may have properties totally unlike ours. Stone many endure eternally, or crumble at daylight...
4. Bodies normally rot away very fast if on the open ground: animals, bacteria etc leave little trace after a few years or much sooner. swamp and wet ground preserves them much longer, peat bogs can preserve bodies in a mummified like state for thousands of years but they will eventually decay.

In my home brew world, a catastrophic war 5 millenia ago left areas of magical devastation, vast, weird ruins etc, but the majority has gone.

Wik,
you mean Megiddo?
http://en.wikipedia.org/wiki/Tel_Megiddo

 

[Insight]

That depends a lot on the nature of the collapse, and the climate of the lands in question.

Consider - the famous Colosseum, in Rome, began construction between 70 and 72 AD. And we can still recognize roads built in Britain by the Romans.

The Great Pyramid of Giza was completed around 2560 BC. The Sphinx is even older. So, major stone objects can persist for several thousand years.

Cave paintings from before human civilization still exist. So, in protected places, things can exist for ten thousand years or more.

Pick anything in between, and you're in the realm of plausibility. The more dry the place, the better things will last.

It's the CLIMATE that plays the biggest role in how long manmade things last. Humidity tends to screw with artificial stuff the most, so I wouldn't place your civilization in a rain forest or a swamp if you want it to be super-old. Deserts are great, as are non-humid mountainous regions, although wind can also play an erosive part in destroying ruins and such.

Skeletons underground should be fine save for a flood or an underground water table thats fairly close to the surface, such as near a river or large lake (or the ocean).

The OLDEST artifacts we have on Earth are around 7,000 years old, and most of them have been found in arid regions. Keep in mind that the majority of archaeologists, historians, and anthropologists agree that civilized humans have been around for around 12,000 years, and have had some form of writing for not more than 7,000 years. The point is that these artifacts have survived at least this long, but we don't have evidence to suggest (or disprove) that such artifacts could have survived longer (20,000, 40,000, 60,000 years?).

The bottom line, though, is that you are free to do whatever you want in your campaign world. How many of your players are scientists? Probably none, so do whatever you want that makes some sense. Also, keep in mind that none of the above factors in the possibility of magic in preserving an item or site from the ravages of time, wind, and humidity.

 

[Ruin Explorer]

Actually, due to the different construction techniques we use now, very few, if any of our structures will be standing for any appreciable length of time. Without constant maintenence, buildings will collapse within decades, bringging other buildings down. After a few centuries, the only thing to indicate there was a major city to the casual observer would be a profusion of non-native plants and animals.

As someone with archaeological experience, I'll believe it when I see it, frankly. To be honest, though, I was thinking more of structures like the Bank of England than Canary Wharf. It's easy to see that structures built on reclaimed land in areas guaranteed to flood won't last forever. However, I don't think it's so clear that buildings in other areas will, particularly ones built in the 1600s-1800s.

 

[Huw]

Ggantija in Malta is claimed to be the oldest free-standing structure in the world. It's over five millenia old and still in pretty good shape. On the other hand, ancient monuments in South East Asia and Indonesia (such as Angkor Wat) a mere millenium old are crumbling away from a mixture of humidity and aggresive plant life.

On a slightly different note, I read that many of the inscriptions in Linear A and Linear B only survived because the clay tablets they were written on were stored in a room in a temple which caught fire, thus baking the clay. Other Minoan records have been lost because the (unbaked) clay they were written on has long crumbled to dust.

So to preserve your ancient civilisation, stick it in a desert. Hot and above all dry are the best preservatives it seems.

 

[Desdichado]

How long does a body last? I'm assuming bones are the last to go. In a temperate environment, buried 6' under - how long until the bones are gone?

That depends on a lot of factors. We've got fossils that are literally hundreds of millions of years old, after all. On the other hand, you can have bodies that don't even last a few weeks before scavengers and microbes reduce them to nothing.

How would runes etched on stone, exposed to the elements, endure?

Exposed to elements? Not very long, I'd say, unless they were extremely deeply carved. Certainly a lifetime measured in centuries at best. Not thousands of years.

Some protection from the elements, and you can go a lot longer, though. Cool dry caves in arid regions, for example---stuff can mummify naturally and last practically forever.

 

[Obryn]

It's all about material, climate, vegetation, and animal life.

Stuff that's not made out of stone in a rain forest will tend to decay & rot away very quickly. Stuff made of stone in a rain forest can still erode rather swiftly. Plants are quite good at breaking stone down into soil, given a few cracks to grow into.

I'd go with somewhere dry, but then you may need to worry about erosion from wind. Blowing sand can take a while, but it'll do the trick eventually.

Overall, though, if you really want to preserve some stuff forever, bury it in a peat bog or freeze it in a block of ice

-O

 

[Morandir Nailo]

The OLDEST artifacts we have on Earth are around 7,000 years old, and most of them have been found in arid regions. Keep in mind that the majority of archaeologists, historians, and anthropologists agree that civilized humans have been around for around 12,000 years, and have had some form of writing for not more than 7,000 years. The point is that these artifacts have survived at least this long, but we don't have evidence to suggest (or disprove) that such artifacts could have survived longer (20,000, 40,000, 60,000 years?).

It's a bit nit-picky, but this is far from the truth. Anatomically modern humans have been around for almost 200,000 years, and have been making objects the entire time, as did their ancestors. There's a hand-axe in the British Museum that's about 1 million years old. More recently, there are plenty of artifacts present from the last Ice Age (ended app. 12,000ya). These objects are for the most part stone and bone tools, though in some areas (Monte Verde in Chile, for instance) organic materials have been preserved. As others have mentioned, cave paintings exist in Europe that are up to 32,000 years old.

One thing to remember is that you're playing in a fantasy world. Obviously, we gamers take for granted that the laws of physics work much as they do on Earth (excepting magic, of course), but that doesn't have to be the case. It's not very hard to imagine a place where materials exist that simply don't wear down, or take tens of thousands of years to do so. And there's always the old fall-back of "it's magic, that's why it's still here after a million years!"

Mor

 

[Ydars]

Materials are very important to the longevity of any object; stonehenge is made of Sarcen stone; one of the hardest stones on earth. This is probably why it is essentially undamaged.

Runes carved into stone in the dark ages are now pretty hard to read in many places, expecially in cold temperate climates like northern Europe, but in other instances are still perfectly readable e.g. some scandinavian carvings; so nearly 2000 years is probably fine.

Proper construction methods mean that stone buildings would last many thousands of years if they are not robbed out; a pity so many buildings in the UK have been destroyed by this practise.

Preservation of bones etc is much more dependent on conditions; acid or dry or cold climes preserves bones but they can also completely decompose within a few hundreds years if conditions are hot and wet; remember we do find bones from a long time ago, but how many out of all the humans that existed in any period have we found; not very many.

 

[Hawkeye]

Are you talking just structures or cultural effects? Ancient cultures from thosuands of years ago still affect us to this day.

Hawkeye