when a skyscraper becomes its own city

A city within a single massive building has been a staple of science fiction and a dream for many designers. Unfortunately, for them, it seems no one actually wants to live in one for a number of good reasons.

Humans can sure take up a lot of space. Not literally mind you, if you stacked humans in pods just big enough to accommodate the average person and raise them 50 units high, the entire global population would comfortably fit within the Bronx metro area, with 23 square kilometers left over. For those curious, yes, I actually did the math. I know, I'm a nerd. But like all abstract calculations, this is technically correct but very much irrelevant since we don't live in pods with a few inches of wiggle room in every direction, we like to have our space. This is why even a high density megacity can take up as much as 7,000 square miles. Start adding in suburbs, exhurbs and other bordering towns that seem to merge with our biggest cities, farms that feed the many millions living in this area, and you end up with vast swaths of space dedicated to perpetuating countless humans with the substantial environmental costs that entails. So what if, asked many architects over the years, we were to consolidate entire cities in massive skyscrapers?

Now the idea is sound if your first priority is efficient allocation of resources. While no huge city could be perfectly efficient, on average, any megacity could concentrate resources and shorten supply chains. This can mean less waste, more productivity, and more economic activity. But if we take it one step further and start structuring them around giant, self-contained skyscrapers, we can wring out many of the current remaining inefficiencies in resource allocation. A vertical farm in each skyscraper would double as green space and the perfect place for producing a lot of staple crops that instead of being delivered across a country are delivered to a different floor which saves a lot on infrastructure costs. From a utopian perspective, embracing growing your own crops in a vertical community garden inside a giant building that also has apartments, bars and nightclubs, movie theaters, schools, and offices could return many millions of square miles back to nature should every city in the world make that leap. But would that ever happen?

Today, such a transition would be politically dead on arrival and technically hard to execute. It's not for a lack of ideas though; within the last 30 years there have been no shortage of plans to build these cities in a skyscraper including Sky City 1000, Shimizu TRY Pyramid, and just a few weeks ago, Sand Sky City. But just because there are plans doesn't mean there's enough raw materials to actually build these projects or money to afford them. Between buying all the land required to pour the foundations, or in the case of Sand Sky City, establish robust routes to get materials to a job site in the middle of nowhere, even getting started comes with a price tag few governments could afford, and those that could, probably have many other uses for the money, ones that will be much more popular with their constituents. Speaking of which, how do you get people to live in these skyscrapers in numbers that make them economically viable?

One rather popular conspiracy theory here in the United States is that extreme urban planning proposals like this are really the machinations of an evil cabal trying to enslave humanity for an amazingly wide array of sinister purposes, so there go millions of potential residents. Plus, how many people would be fine with giving up their privacy, living with over a million others not just around them, but in the same building at any given time? Just like flying cars look great from a purely utilitarian, utopian point of view, the reality of actually creating them is fraught with many problems that will take a long time to address. Maybe at some point in the far future, with more globalized economies and massive changes in culture, buildings housing an entire city could be viable, and by then we're bound to have plans for hundreds of them. But we're not going to get them anytime soon. They simply cost too much, require too much, and unlikely to provide the kind of return on investment we'd need to make them worthwhile. At least for now…