I don’t think there’s any danger of that happening. As far as I can tell, it looks exactly as “finished” as it was when I visited there over 30 years ago.
You also have to consider things like the situation with the Buddha carvings in the Afghan wilderness. They probably would have lasted a very long time, had the Tealiban not decided that they needed to be destroyed.
I gotta go with Hoover Dam. Massive and thick concrete not exposed to salt.
I remember some (american, in fact) documentary about how things would eveolve if men suddenly disapeared. I remember there was a part about the Hoover Dam. And IIRC, lacking maintenance, it was doomed to eventually collapse after maybe some hundred of years.
In fact, I believe that concrete in general doesn’t pass well the test of time, hence that any structure build with concrete won’t last that long.
Was there anything large build recently with stone blocks?
I think most concrete structures above the snowlines are going to die an early death due to the freeze/thaw cycles and will be overgrown pretty quick. You are probably looking for something in a fairly arid environment.
The Washington Monument among others. An earthquake is likely to topple it eventually.
It will be a Starbucks.
I think I remember reading something about the Hoover Dam sitting on a fault line. If so, I wouldn’t lay odds on it survivng intact for more than a couple hundred years.
Also, what I’ve heard about the construction of the 3 Gorges Dam doesn’t fill me with confidence. You couldn’t possibly pay me enough money to live anywhere below it :eek:
In general, I think dams of any kind are a bad bet. Nothing can hold back a wall of water forever.
Something in a dry climate.
I could see, maybe, something like Glen Canyon Dam breaching at the base, up just enough to clear the free-running river, but leaving the upper portion of the structure intact.
What about some of Las Vegas? The buildings would probably lose their glass in the first century, but there’s minimal causes for erosion. I think at least some of them would be recognizable for a long time, for much the same reason ancient Egyptian stuff is still around.
On the other hand, some of our missile silos and other underground structures might remain as long as Newgrange, no desert conditions required.
Something on top of a tall mountain in an arid environment. Anything subjected to water and freeze-thaw is going to crumble in a few hundred to a few thousand years. There are intact flesh mummies in mountain caves over 500 years old.
I think I saw this on Life After People. I’m betting on Rushmore or Stone Mountain.
The Germans built a lot of large, long lasting structures before and during WWII.
Some of the most impressive are submarine pens, several of which are still standing because it would just take too much effort to remove them. The factory/pens near Bremen aren’t going anywhere anytime soon on their own.
Even “small” structures like flak towers seem stable in the long term.
Does the Long Now count? It’s designed to last 10,000 years.
Actually, without proper maintenance, I wouldn’t give the Boeing facility long. Something that huge has a lot of roof space and if that roof isn’t maintained, it’ll soon develop leaks and that wouldn’t be good news for the steel girders just below, especially in our wet climate.
I’m thinking something like the huge concrete grain silos at the Port of Seattle. Only in a drier place. And with less chance of big earthquakes. Being well reinforced, and clustered together like they are (so if one begins to lean, it can’t go far) I should think they’d be around for quite a while.
In that context, the world’s largest grain elevator (silo) is near Hutchinson, KS. Drier, mostly, and away from fault lines. Does have more risk from tornadoes, though.
It’s supposed to function for 10,000 years, so I’d kinda hope it’s still recognizable as a building at that point.
I don’t know for sure, but it would probably be something in a very dry place, isolated from wind, water, rain, salt, smog, etc. – all the things that tend to cause wear and thus require maintenance. Voyager, if it could be counted as a structure, is about as isolated as you can get. But I don’t think I personally would count that as a structure. Others are welcome to.
So here it is: Launch the Sears Tower (or your structure of choice) into space away from the center of the galaxy, with no stars along its path, and it might last nearly forever. Certainly, it could last longer than the earth itself. It’s not a practical answer, but if you wanted practical answers, you would be asking an architect or a scientist, and not the Straight Dope community.
I think this is an important distinction. Remaining standing with constant maintenance is a different ball game from remaining standing after a hypothetical sudden disappearance of humanity. Or, for that matter, remaining standing after being scavenged for parts in a post-apocalyptic Mad Max scenario.
Are we assuming a post-civilization type of situation here?