# What will be the largest post-industrial man-made structure to remain standing the longest? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [March 20, 2015, 1:48am UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443 "2015-03-20T01:48:55Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![DCnDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dcndc/32/2842_2.png) [@DCnDC](https://boards.straightdope.com/u/DCnDC)\ **Post date:** [March 24, 2015, 11:57am UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/41 "2015-03-24T11:57:17Z")
> [@Martian Bigfoot](#): > > Are we assuming a post-civilization type of situation here? Not necessarily. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [March 24, 2015, 12:12pm UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/42 "2015-03-24T12:12:24Z")
If Mount Rushmore will last a long time, how about **Stone Mountain** in Georgia? It was originally designed by Borglum, who did Rushmore, and it’s farther south, so it sees less freeze/thaw. [http://lessbeatenpaths.com/tag/strange-pyramid-in-north-dakota/](http://lessbeatenpaths.com/tag/strange-pyramid-in-north-dakota/) > **[Stone Mountain](https://en.wikipedia.org/wiki/Stone_Mountain)** > > Stone Mountain is a quartz monzonite dome monadnock and the site of Stone Mountain Park, 16 miles (26 km) east of Atlanta, Georgia. Outside the park is the small city of Stone Mountain, Georgia. The park is the most visited tourist site in the state of Georgia. > The park is owned by the state of Georgia. At its summit, the elevation is 1,686 feet (514 m) above sea level and 825 feet (251 m) above the surrounding area. Stone Mountain is well known for not only its geology, but also the enormous ro... Actually, there are many large bas-relief structures in the Old World that have already lasted many thousands of years. I have to admit that I don’t classify them as buildings. The pyramids in Egypt and elsewhere, Stupas in India, and other such structures are very old and very stable because they’ve essentially already “fallen down”. aside from possible interior passages, they’re basically just big piles of stone. They’re about as stable as you can get. The pyramids have already outlasted earthquakes that toppled other Wonders of the Ancient World. They’ll probably outlast any modern skyscrapers, the supporting steel of which can eventually rust. > **[The Essential Guide to Modern Pyramids](https://www.atlasobscura.com/articles/the-essential-guide-to-modern-pyramids)** > > The pyramids of the ancient world are some of the most enduring icons of our planet’s past. From the remnants of the Mayan civilization to the famous... A long-lasting modern structure would be one built of stone in a stable configuration like the pyramids, ideally in some dry desert location. There are a lot of concrete structures, but concrete tends to crumble through time. Most modern pyramids are hollow and constructed of steel and the like, and so aren’t good candidates. So the pyramid in Memphis, Luxor in Vegas, and many others won’t last. Mary Baker Eddy’s monument in Bow New Hampshire was a solid rock pyramid. It probably would have been a good candidate, if someone hadn’t blown it up with dynamite. [https://images.search.yahoo.com/images/view;\_ylt=AwrB8pOkUhFVASMAb0OJzbkF;\_ylu=X3oDMTIyZzhtY3V0BHNlYwNzcgRzbGsDaW1nBG9pZANmMDViNzEwNTdhYTRhYzk4MDBiMTczMDA3NjQxYTk0NARncG9zAzcEaXQDYmluZw--?.origin=&back=https%3A%2F%2Fimages.search.yahoo.com%2Fsearch%2Fimages%3Fp%3DPyramid%2BMary%2BBaker%2BEddy%26fr%3Dyfp-t-252%26tab%3Dorganic%26ri%3D7&w=1168&h=1268&imgurl=thearkoftruthmothershood.files.wordpress.com%2F2012%2F06%2Fpyramid-capstone-at-bow.png&rurl=http%3A%2F%2Fthearkoftruthmothershood.wordpress.com%2F2012%2F06%2F19%2Fdrawings-and-pictures%2F&size=1375.2KB&name=From+–+Landmarks+From+Bow+to+Boston+–+published+by+the+CSPS&p=Pyramid+Mary+Baker+Eddy&oid=f05b71057aa4ac9800b173007641a944&fr2=&fr=yfp-t-252&tt=From+–+Landmarks+From+Bow+to+Boston+–+published+by+the+CSPS&b=0&ni=288&no=7&ts=&tab=organic&sigr=12ffp1gjo&sigb=135eo5933&sigi=12gqefbpr&sigt=11v97rqsi&sign=11v97rqsi&.crumb=iFnxBO8CwGG&fr=yfp-t-252](https://images.search.yahoo.com/images/view;_ylt=AwrB8pOkUhFVASMAb0OJzbkF;_ylu=X3oDMTIyZzhtY3V0BHNlYwNzcgRzbGsDaW1nBG9pZANmMDViNzEwNTdhYTRhYzk4MDBiMTczMDA3NjQxYTk0NARncG9zAzcEaXQDYmluZw--?.origin=&back=https%3A%2F%2Fimages.search.yahoo.com%2Fsearch%2Fimages%3Fp%3DPyramid%2BMary%2BBaker%2BEddy%26fr%3Dyfp-t-252%26tab%3Dorganic%26ri%3D7&w=1168&h=1268&imgurl=thearkoftruthmothershood.files.wordpress.com%2F2012%2F06%2Fpyramid-capstone-at-bow.png&rurl=http%3A%2F%2Fthearkoftruthmothershood.wordpress.com%2F2012%2F06%2F19%2Fdrawings-and-pictures%2F&size=1375.2KB&name=From+%E2%80%93+Landmarks+From+Bow+to+Boston+%E2%80%93+published+by+the+CSPS&p=Pyramid+Mary+Baker+Eddy&oid=f05b71057aa4ac9800b173007641a944&fr2=&fr=yfp-t-252&tt=From+%E2%80%93+Landmarks+From+Bow+to+Boston+%E2%80%93+published+by+the+CSPS&b=0&ni=288&no=7&ts=&tab=organic&sigr=12ffp1gjo&sigb=135eo5933&sigi=12gqefbpr&sigt=11v97rqsi&sign=11v97rqsi&.crumb=iFnxBO8CwGG&fr=yfp-t-252) > **[HEALING THE SICK A MEANS, NOT AN END](https://www.angelfire.com/sc3/csresources/pyramid.htm)** > > information, Christian Science, study system, literature But there are vplenty of other pyramids in America that will stand a long time, like the Ames brothers pyramid: > **[Ames Brothers Pyramid, Buford, Wyoming](https://www.roadsideamerica.com/story/2259)** > > The Ames Brothers were fatcat 19th century industrialists, now as forgotten as the lonely, towering sagebrush pyramid that was built in their honor. > **[Buford, WY - Ames Brothers Pyramid](https://www.roadsideamerica.com/tip/2259)** > > Visit reports, news, maps, directions and info on Ames Brothers Pyramid in Buford, Wyoming. …or Arizona Governor Hunt’s pyramid tomb: > **[Buford, WY - Ames Brothers Pyramid](https://www.roadsideamerica.com/tip/2259)** > > Visit reports, news, maps, directions and info on Ames Brothers Pyramid in Buford, Wyoming. … or maybe this missile silo pyramid (although I suspect it’s made of reinforced concrete, not stone): [http://lessbeatenpaths.com/tag/strange-pyramid-in-north-dakota/](http://lessbeatenpaths.com/tag/strange-pyramid-in-north-dakota/) ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [March 24, 2015, 2:42pm UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/43 "2015-03-24T14:42:01Z")
It’s man made. It actually stands. And they will probably last until the sun goes into its red giant phase. The base structures of the Lunar Exploration Modules. And there are handful of them for redundancy. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [March 24, 2015, 3:11pm UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/44 "2015-03-24T15:11:41Z")
> [@billfish678](#): > > It’s man made. It actually stands. And they will probably last until the sun goes into its red giant phase. > > The base structures of the Lunar Exploration Modules. And there are handful of them for redundancy. Some of these post-industrial pyramids are bigger. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [March 24, 2015, 3:12pm UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/45 "2015-03-24T15:12:57Z")
I did not know that. ---
**Author:** ![itsfunhavingfun](https://avatars.discourse-cdn.com/v4/letter/i/b5e925/32.png) [@itsfunhavingfun](https://boards.straightdope.com/u/itsfunhavingfun)\ **Post date:** [March 24, 2015, 6:22pm UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/46 "2015-03-24T18:22:27Z")
> [@Haldurson](#): > > 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. Whatchu talkin’ 'bout, Willis? ---
**Author:** ![Mr.Nylock](https://avatars.discourse-cdn.com/v4/letter/m/77aa72/32.png) [@Mr.Nylock](https://boards.straightdope.com/u/Mr.Nylock)\ **Post date:** [March 24, 2015, 6:25pm UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/47 "2015-03-24T18:25:19Z")
Kim kardashian ---
**Author:** ![Malthus](https://avatars.discourse-cdn.com/v4/letter/m/85f322/32.png) [@Malthus](https://boards.straightdope.com/u/Malthus)\ **Post date:** [March 24, 2015, 6:30pm UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/48 "2015-03-24T18:30:41Z")
Road or railroad cuttings through stable bedrock, like the Canadian Shield. My guess is that they will last until glaciation wipes them out. ---
**Author:** ![Pabitel](https://avatars.discourse-cdn.com/v4/letter/p/bbce88/32.png) [@Pabitel](https://boards.straightdope.com/u/Pabitel)\ **Post date:** [March 24, 2015, 6:58pm UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/49 "2015-03-24T18:58:42Z")
> [@clairobscur](#): > > 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. They had a better formula than ours but there are Egyptian and Roman concrete structures that are still recognizable thousands of years later, including the Colosseum, which is still certainly recognizable and is almost 2000 years old. [cite](http://archserve.id.ucsb.edu/courses/arthistory/152k/concrete.html) ---
**Author:** ![LAV25](https://avatars.discourse-cdn.com/v4/letter/l/97f17d/32.png) [@LAV25](https://boards.straightdope.com/u/LAV25)\ **Post date:** [March 31, 2015, 1:43am UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/50 "2015-03-31T01:43:53Z")
One of the things that “Life After People” mentioned that was a surprise to me is that “reinforced” concrete will have a shorter lifespan than simple poured concrete, because it’s reinforced by pouring it over and around steel rebar. Eventually, water will make it’s way in, and the rust expansion will crack the material around it. One of the episodes featured a sound studio in…uh, L.A.? Anyway, non-reinforced, so they said it would last longer than a lot of the buildings around it. ---
**Author:** ![LAV25](https://avatars.discourse-cdn.com/v4/letter/l/97f17d/32.png) [@LAV25](https://boards.straightdope.com/u/LAV25)\ **Post date:** [March 31, 2015, 1:52am UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/51 "2015-03-31T01:52:15Z")
Here we are: [Oxide Jacking](http://en.wikipedia.org/wiki/Oxide_jacking#Damage_to_reinforced_concrete_bridges_and_buildings) ---
**Author:** ![robert\_columbia](https://avatars.discourse-cdn.com/v4/letter/r/e79b87/32.png) [@robert\_columbia](https://boards.straightdope.com/u/robert_columbia)\ **Post date:** [March 31, 2015, 2:01am UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/52 "2015-03-31T02:01:41Z")
> [@TriPolar](#): > > … > > What about canals? How long would it take for the Suez to silt up so that water no longer flowed through?.. The C&O Canal is in pretty bad shape, especially as you get into the middle of rural Pennsylvania and such where it isn’t cutting straight through an urban area like it does in DC. Many areas aren’t even that wet, are currently without walls, and are basically a small valley that might be otherwise unremarkable except for the fact that it goes on for miles and miles. Give it a thousand years, and it’s gone. ---
**Author:** ![robert\_columbia](https://avatars.discourse-cdn.com/v4/letter/r/e79b87/32.png) [@robert\_columbia](https://boards.straightdope.com/u/robert_columbia)\ **Post date:** [March 31, 2015, 2:05am UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/53 "2015-03-31T02:05:24Z")
> [@eschereal](#): > > How sturdy is the Pentagon? I also suspected the Pentagon. Big advantages are the fact that it’s not that tall and is very wide, so it’s much less likely to be obliterated by collapsing roofs or walls. Consider that it received a direct hit on 9/11 that only destroyed a small part. ---
**Author:** ![dahl.winterle](https://avatars.discourse-cdn.com/v4/letter/d/9d8465/32.png) [@dahl.winterle](https://boards.straightdope.com/u/dahl.winterle)\ **Post date:** [April 2, 2015, 4:07pm UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/54 "2015-04-02T16:07:34Z")
In regard to Hoover Dam, I’ve heard that the expected fate is that, once the dam is no longer maintained, the Colorado will silt-up behind the dam and turn it into a waterfall, long before it would collapse. Whether this means it is recognizable is the next question. I’ve seen a couple of smaller dams in Pennsylvania that have done this. ---
**Author:** ![dahl.winterle](https://avatars.discourse-cdn.com/v4/letter/d/9d8465/32.png) [@dahl.winterle](https://boards.straightdope.com/u/dahl.winterle)\ **Post date:** [April 2, 2015, 4:16pm UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/55 "2015-04-02T16:16:43Z")
The Suez and Panama canals require constant dredging. The Suez is a sea-level canal through the Saudi sands, connecting two fairly calm bodies of water, but the sand shifts/blows/migrates/moves. The Panama Canal is (from the Pacific) two locks (Miraflores and Pedro Miguel), eight or so miles of actual cut/canal, a dammed lake, an artificial inlet, another lock (Gaillard) and then a natural bay. ---
**Author:** ![Diceman](https://avatars.discourse-cdn.com/v4/letter/d/22d042/32.png) [@Diceman](https://boards.straightdope.com/u/Diceman)\ **Post date:** [April 2, 2015, 4:31pm UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/56 "2015-04-02T16:31:16Z")
> [@dahl.winterle](#): > > In regard to Hoover Dam, I’ve heard that the expected fate is that, once the dam is no longer maintained, the Colorado will silt-up behind the dam and turn it into a waterfall, long before it would collapse. Whether this means it is recognizable is the next question. I’ve seen a couple of smaller dams in Pennsylvania that have done this. If this happens, the flow of water will begin to erode the dam from the top down. Eventually (probably thousands or millions of years), the river would carve a channel thru the dam. ---
**Author:** ![Gunslinger](https://avatars.discourse-cdn.com/v4/letter/g/4491bb/32.png) [@Gunslinger](https://boards.straightdope.com/u/Gunslinger)\ **Post date:** [April 2, 2015, 11:37pm UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/57 "2015-04-02T23:37:19Z")
> [@Trinopus](#): > > Serious answer: a set of concrete storage buildings…somewhere. Maybe a “U-Stor” in Baltimore, or in Duluth, or in Brisbane… But a row of concrete storage blocks. There’s hundreds of thousands of 'em, and they’re just about as solid as can be, while also fairly minimal. They aren’t complicated enough to fail in any fancy way. I’d imagine the [Nazi flak towers](http://en.wikipedia.org/wiki/Flak_tower) around Berlin, Hamburg, and Vienna might have similar longevity to the Pyramids, being giant monolithic thick-walled concrete fortresses. – you’ll note that the majority of them are still standing, and the ones that were demolished required _a lot_ of explosives to take down, and mostly serve as the bases of artificial hills, because, great, you blew it up. Now what are you going to do with thousands of tons of concrete boulders? See also the various u-boat pens that weren’t demolished after the war. The Nazis built things to last despite the Brits and Americans bombing them weekly – think of it as accelerated weathering, like how cars are put under heat lamps and pressure sprayers to test in a few days how the paint will hold up until the warranty runs out. Without the bombs, that stuff will last a long time. Not _quite_ as long as the Pyramids, though – the problem with concrete in those northern climes is that once it gets a crack, water seeps in, and the freeze/thaw cycle slowly presses the crack wider until it gets down to the steel rebar, which then rots out and provides convenient spaces for the ice to tear it apart. But, as discovered by the Brits after blowing up the flak towers, it still leaves a gigantic pile of broken concrete with flat bits and right-angled corners that obviously used to be a building. So, habitable for a thousand or two years, but visibly manmade ruins on a geologic timescale. Dammit, beaten, but I spent so much time and effort on that last bit I’m leaving it. > [@Musicat](#): > > Considering the state of some roads I drive over daily, that were paved less than 10 years ago, a road might not out-last much of anything after a few hundred years. The roads themselves won’t last in drivable condition (I think the spec for the US Interstate system was 50 years, and now it’s been 60 and we don’t have the money to redo them), but it’ll take quite a while for nature to reclaim the road_beds_ – see the broken concrete thing above, and roads are underlaid by a foot or so of sand and gravel, and poisoned by all the crap that drips out of cars. It’ll be eons before enough trees can grow to blend them in with the surrounding landscape. > [@Malthus](#): > > Road or railroad cuttings through stable bedrock, like the Canadian Shield. My guess is that they will last until glaciation wipes them out. Nah, once you take the dirt off it’s exposed to wind and water, and will eventually fill up with dirt. It’ll be a valley in an odd place until the next ice age, but will blend in with the tundra pretty quick, aside from the road issues I mentioned above. A bit quicker than the roads out in the flatlands, though, what with the possibility of mudslides from the hills next to it. ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [April 3, 2015, 7:11am UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/58 "2015-04-03T07:11:38Z")
> [@dahl.winterle](#): > > The Suez is a sea-level canal through the Saudi sands, connecting two fairly calm bodies of water, but the sand shifts/blows/migrates/moves. Saudi sands? So the Egyptians are importing sand? ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [April 4, 2015, 3:22am UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/59 "2015-04-04T03:22:48Z")
When freeways are made, the hills are cut down, creating escarpments, the valleys are filled up, creating embankments… these are larger than any flak tower… and may well last a very long time… ---
**Author:** ![RTFirefly](https://avatars.discourse-cdn.com/v4/letter/r/c77e96/32.png) [@RTFirefly](https://boards.straightdope.com/u/RTFirefly)\ **Post date:** [April 4, 2015, 11:12am UTC](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443/60 "2015-04-04T11:12:44Z")
> [@robert\_columbia](#): > > I also suspected the Pentagon. Big advantages are the fact that it’s not that tall and is very wide, so it’s much less likely to be obliterated by collapsing roofs or walls. Consider that it received a direct hit on 9/11 that only destroyed a small part. > [@DCnDC](#): > > there should be enough of it remaining that it would still be instantly recognizable for what it was to a person living today. The Pentagon was the first thing that came to my mind as well. Even after the ravages of time and weather reduce it to rubble, it’ll still be a Pentagon-shaped pile of rubble for a good long time. [Previous page](https://boards.straightdope.com/t/what-will-be-the-largest-post-industrial-man-made-structure-to-remain-standing-the-longest/715443.md?page=2)