248

Fran is a naturally subterranean boring worm-like creature. Her cilia enable her to move forward and rotate. On her homeworld, the tunnels are bored with ridges or grooves that serve as affordances for forward locomotion, allowing her species to progress along the intended direction of the tunnel (forward) more easily (and conversely, making it more ...


188

Human engineering can, 100%, keep out a horde of zombies. In The Walking Dead things fail because if they didn't the show would be boring. In real life, there exist castle gates hundreds of years old which would hold, no questions asked. First and foremost, realize that thousands of zombies will never be pushing on the gate all at the same time. They will ...


134

Build a Pyramid The Pyramids are halfway to your desired 10,000 year life span already. They are a little worse for wear, but they are definitely still standing. First, lets assess the criticism that the pyramids are not skyscrapers. The great pyramid at Giza (139m) was the tallest building in the world until the Lincoln Cathedral was completed in 1311. ...


134

TL;DR: Really, really big (exact numbers below) Seeing the wall "crossing" is hardly the issue. Seeing the outer wall bend even slightly toward the inner wall - looking as if the hallway gets narrower further on - and the point at which that visually happens moving ahead at the rate at which you are moving already breaks the illusion of a straight surface. ...


110

We humans are pretty good at building gates to keep people out. We've been doing it for a long time for military purposes and to stop thieves. Why Do We Have Gates? Because there has to be some way for friendlies to get through the defenses while keeping the bad guys out. From a military perspective, a gate isn't there to stop people from getting in. They'...


99

Forts using stone, rock and earth walls as fortifications (and in some cases, still standing !) were often attacked during sieges. Such a wall has much in common with a dam. To breach such a wall you tunnel underneath. It's a well established technique. You dig a tunnel, using normal techniques to prop and seam your tunnel. Then when you've dug enough, ...


90

There are a few languages on earth that don't have words for relative direction. Instead of they use absolute the directions North, South, East, and West to describe the positioning of things. For example; speakers of these languages when facing East, would refer to their "North foot" and "South foot", and if they turned 90 degrees would refer to their "East ...


84

The body shape of the aliens makes it difficult to pull doors open, but they can easily push doors open (or vice versa). Have you ever tried to get through a door with both hands full? The aliens' body shape has the same effect. So doors are generally designed in pairs for both directions.


76

This is my solution, right here: Preferably in a rainy area of the country, like Seattle. But even somewhere like California, that actually receives enough rainwater to resupply itself but throws it away with flood control would probably work well enough if you were willing to ration. Consider the needs: Construction supplies for fortification and for ...


67

A more devious scheme to bring a dam down: A secret second dam above the main target dam. You simply install a second dam above the main dam (as high as possible ideally). You reduce the flow inconspicously so that the main dam manning do not see anything unusual, but slowly the reservoir of your second dam is filling. Now you wait for the perfect time ...


66

Your society has a hypermartial warrior culture. The double-doors eliminate the problem of accidental rudeness and slaughter. If you were to attempt the use of a door at the same time as me, one of us must either retreat for the other or turn their back to walk out of the way. One is a dishonour to me: retreat is never acceptable. The other is an insult to ...


58

Heights would not be dangerous Because there is little risk of injury from falling, the creatures would not suffer from vertigo. Our skyscrapers have walls around them to stop people from falling. Non-structural guards would not be required. Birds quite happily perch in locations that would be terrifying for a human. A pigeon will sit on the windowsill of ...


57

Well as I see it you have two potential options. Buy a Caribbean island and relax away the zombie apocalypse on the beach with rum and grass skirts. Build a massive fortress. While option 1 is far and away the better choice it isn't very interesting... So. What would this fortress need? Where? Geographically isolated...the farther away from "...


57

Self-healing concrete. It works by embedding tiny capsules in the concrete containing bacterial spores. When the capsules are broken by water penetrating the concrete, the bacteria are released and begin to metabolise - and one of their waste products is calcite (a component in limestone). The calcite seals the crack, good as new. The technology is ...


55

From walking by casually? Easy. If you assume it needs to remain hidden from the valley below, you just need to place any entrances, windows, etc., behind a curve. I think your biggest issue by far is the population of 5000. That's a lot of people to feed and hydrate. But we're ignoring that problem for the most part I read. So, before we design the ...


52

Core-scrapers Buoyancy is a problem. The main issue with getting a building that deep is the water table. If you build something deep under the water table and want that thing to be full of air, it will really want to float. This is even a problem with recently buried coffins during floods. So, if the building is being built where people typically live (...


52

Put the temple in medium earth orbit This has many convenient effects for your goal of slaughtering an aspiring archaeologist: You don't have to have as many layers of traps, because only a few explores will have the means to reach your temple in the first place Traps that would be mildly inconvenient on earth are extremely deadly in space if you are ...


52

Consider the real world underground city of Derinkuyu in Turkey They stumbled on a simple solution, a giant stone disc in a groove for a door. Easy to move and brace from the wide interior room but impossible to move from the narrow entrance passage. The narrow bendy entrance made it nearly impossible to break through from the outside without spending ...


47

Stone Buildings are Hard to Burn This is no joke- if you want your home to be resistant to fire, use stone or ceramics (clay) to form the load-bearing parts. As a small anecdote: I have lived in Europe, and once in a mostly stone home, which experienced an electrical fire. What did the fire department do? Tell us to simply keep flammables away from the fire,...


47

I am not really malicious enough to spend my time designing booby traps. So instead I'll just present how a nice person such as myself would built a treasure vault for reference. It should be filled with chemically inert gas for protection. To avoid leaks the gas should be heavier than air and the vault built well below ground level in an are with very ...


47

Feng Shui! In the traditional Chinese Architecture: The main gateway entrance into the courtyard house had two red doors; it was located on the eastern part of the south side conforming to the rules of feng shui. Immediately behind the entrance was a solid wall '照壁 zhào bì' that denies direct view or access to the courtyard, in Feng Shui terms it was to ...


46

Make a balloon. All you need is some decent silk/linen, ropes, some basket, and then something to heat up the air inside. Heat the air, unstick the balloon, but take some rope with you so you won't fly away. Wait for right wind direction, fly over the island, land there (make a hole, or wait, or let someone rope down and anchor you and then wait). Now you ...


46

SRM points out that even in a circle long enough that you won’t reach your starting point again if you're walking for an hour, and where you can’t see very far, one can still tell that the walls are curved. So, hide that better. Make the path wavy, and the walls are even rougher. Any given visible wall may be convex or concave to varying degree. The bias ...


45

Let's revisit the premise that the sky-castle has a year's worth of water stored on it. As a corollary to this premise, we should assume that the stored water won't become stagnant or otherwise undrinkable. With minimal bathing and cleaning, just cooking and drinking and basic hygiene, the castle's smelly troopers still require about 5 gallons (16 L) of ...


41

How about the rationality of object persistence? She doesn't have to know left from right; she knows the lemonade stand exists and will continue to exist if it is out of her sight. Infants know this within a few months. Thus: Turn. Left or right, randomly chosen, does not matter. If the lemonade stand is no longer visible; rationality tells you it is behind ...


41

From a safe distance, your sappers excavate a tunnel. The tunnel leads to the tether point of the castle's anchor chain. Bring the tether down into the tunnel from below. Winch it along the tunnel. You will winch the castle downwards. Defenders of the sinking castle will see their chain disappearing into a hole. They can rappel down and enter the hole ...


39

Start with the people then the city then the ruins Cities always arise from the culture and situation of the people who built it. Their priorities will be expressed in what buildings are where and what they look like. Modern skyscraper-filled cities emphasize maximal value per square foot. Hobbits for some reason really liked round doors to their homes. ...


38

You have solar power, I presume you have reasonably intelligent robots, the solution is to take a clue from biology: Constantly, whether it is needed or not, replace every molecule of the space station with newly fabricated parts, smelt down the old parts, bring in new steel or whatever from asteroids. Make so no part of your station is ever more than 20 ...


38

Prototaxites! Fossil mushrooms are rarities. Mushrooms are the fungal equivalent of flowers - spongy, ephemeral, disposable bodies generated to serve a reproductive need. You could not use mushrooms for wood. The prototaxites were not mushrooms. They were large and substantial; up to 7 meters high. https://www.smithsonianmag.com/smart-news/long-...


37

I don't think an inanimate building is an option either. I'm going to admit this may not be within the technological scope you want, it certainly wouldn't exactly look the way you want and there are some real issues about why this would be a desirable choice, but if you're willing to stretch, how about a genetically modified tree. The current tallest ...


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