This news is approximately three hundred million internet years old (I saw it Monday), but it hasn't been on Slog yet.

Treehugger reports that a firm called Broad Sustainable Construction has obtained final approval to begin, starting a June, building a 220-story tower in Changsha, China, that reaches a half mile high, making it the world's tallest building. Ominously, they're giving it the same name as that bland restaurant on top of the Space Needle: Sky City.

Unlike decorative towers that serve airplane food and trophy skyscrapers like the Burj Khalifa, this Sky City is supposedly functional, affordable, and comparatively inexpensive to build. Many components of the pre-fab modular construction are being built off site, so the on-site construction schedule is only about three months. "It all just bolts together," writes treehugger. "BSC claims that by building this way, they eliminate construction waste, lost time managing trades, keep tight cost control and can build at a cost 50% to 60% less than conventional construction."

But the description gets a little breathless. "By using elevators instead of cars to get to schools, businesses and recreational facilities, thousands of cars are taken off the roads and thousands of hours of commuting time are saved," they gush, adding that it will include nearly one million square feet of vertical organic farms. "The numbers continue to stagger. In one building, there will be accommodation for 4450 families in apartments ranging from 645 SF to 5,000 SF, 250 hotel rooms, 100,000 SF of school, hospital and office space, totaling over eleven million square feet. The building footprint is only 10% of the site; the rest is open parkland."

Here's a video:

I'm admittedly enchanted—it's a giant, modular arcology, you guys!!—but the pinnacle of density is not the pinnacle of destiny. In fact, it's arguably a relic of the past (towers in the park, anyone? and care to live in a mall?), and even if it's less expensive than other super skyscrapers, high rises are always more expensive to build and more complicated to finance than low-rise buildings, which provide ample density for a city and relate better to the street. Still, it's an amusing experiment in super-high-density-construction that isn't just for the rich. Though I doubt those 210th story penthouses are gonna be doled out to proles, either.