"A chair is a very difficult object. A skyscraper is almost easier." --Mies Van de Rohe, legendary architect.
By that logic, a colossal 2 kilometer high mega-structure should be really easy to visualize and put together. Of course, this is exaggerated and only meant to emphasize thoughtfulness in design. But speaking of immense skyscrapers... We've already talked about gigantic city-structures of Paolo Soleri. Today we are going to see more gigantic and highly imaginative chairs... er, no, mega-structures that were proposed in the last four decades - plus we are going to briefly look into the past, for a glimpse of glorious retrofuture.
We'll start with the re-imagining of the good old Hoover Dam - which includes a "Tower in a Dam", and looks like something dreamed up by Megatron:
 
This design by UK architect Yheu-Shen Chua has been awarded Third Place in eVolo's 2011 Skyscraper Competition: "One of the main purposes of the project is to allow the water from the upstream river to engage directly with the visitors through a series of containers. A hanging tower above the 700-foot drop into the Black Canyon would be used as gallery and a vertical aquarium."
Belgian Architect Vincent Callebaut dreamed up a combination of skyscraper and airship, where the skyscraper itself floats in the air, feeding on a green "algae" energy: the "Hydrogenase" project is as eco-sustainable, as it is beautiful - more info:

(images credit: Vincent Callebaut)
Vincent Callebaut uses organic shapes in his designs and and dreams BIG - see all of his fantastic projects here.
Floating Observatories: Unreal Tower Proposed for Taiwan
Strange combination of a tree-like skyscraper and huge Zeppelin airship-inspired floating observation decks is a radical vision by Romanian Dorin Stefan Birou Arhitectura - more info and images here





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The flowing shapes of this skyscraper remind us of the work of late Jan Kaplicky: on the left is the new national library in Prague, on the right is his "Future Systems" building -

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The Taipei City Museum of Art concept by OODA is based on two hypercubes and looks like an alien artifact:

Another alien creature-like Taipei concept is proposed for the Performing Arts Center, by B+U design:

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Colossal Projects Conceived in the 1980s-1990s
This is a huge tower that was at one time planned for Moscow (by Norman Foster and Partners):


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In 1995, a truly gigantic structure was conceived for Tokyo: X-SEED 4000 - four kilometers high, 800 floors, the tallest building ever envisioned (on the right). Image on the left shows scaled-down two-mile high tower:


Inside the X-SEED 4000:

on the right is yet another super-building concept for Tokyo, conceiving at the height of Japanese asset price bubble in 1989 - Sky City 1000:

The Shimizu TRY 2004 Mega-City Pyramid was another super structure proposed for Tokyo: "The proposed structure is so large that it cannot be built with currently available materials, due to their weight. The design relies on the future availability of super-strong lightweight materials based on carbon nanotubes."


"Large robots would assemble the truss structure, and air bladders would be used to elevate trusses above the first layer using a construction system proposed by Italian architect Dante Bini. Spheroid nodes at the connections between trusses would provide structural support and serve as transfer points for travelers."

On the left is "Project: Spiral" 1000-meter high, designed for Tokyo in 1998. Right image: Noida Tower concept for Noida, india:

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Jumeira Garden District structures for Dubai (left) and Seoul Commune 2026 project for South Korea (right):

Dating from 1997 is the Bionic Tower concept for Shanghai and/or Hong Kong (with possibility of building the "Bionic Tower Vertical City" 1.228 meters high):

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New Thoughts in Mega-scale Architecture
Algorithmic Architecture! More than just a catchy term, this is a great tool in coming up with organic and nature-inspired forms, based on mathematical algorithms:


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...especially for bridges (more info):

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Boston Arcology (left) is a mega-structure concept by Kevin Schopfer, who also came up with the amazing New Orleans Arcology Habitat (NOAH) (right image, more info). This building was designed using golden proportions and will house 15,000 people:

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The Living Mountain project, again from 2011 Evolo Skyscraper Competition, is created to grace the desert of Taklamakan in northwest China:

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Gardiner Expressway in Toronto is proposed to become the site for mutating "living organism" mega-structure - more info:

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Ocean Arcologies: Floating Mega-Cities
Gigantic skyscrapers and mega-cities can grow not only up high, but deep down in the water. This "Water-Scraper" is a rather creative re-thinking of a floating island idea, made for eVolo design competition - more info:

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Floating cities is not a new concept by any means. Here is a sketch from Popular Mechanics, 1931:

Japanese firm Shimizu also came up with a floating city concept, consisting of floating islands, or rather the "lily-pads" drifting in the equatorial Pacific:

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On the left is illustration by Paul R. Alexander from the article "Energy from the Ocean: A Resource for the Future", 1989"... On the right: City on the Sea, architect: Eugene Tsui -

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To give you an idea of the UNDERGROUND super city, here is art from Astounding Stories, November 1937:

Other Elegant Proposed Skyscrapers
Organic forms of all varieties seem to be all the rage nowadays: on the left is "Tree of Life" skyscraper by Ukraine architects (info); on the right is the fantastic "Hydra", which can take energy from... lightnings!
Imaging living in a place that is designed to be struck by lightnings... in a safe manner, of course (more info)

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The "Hydra", designed by Milos Vlastic, Vuk Djordjevic, Ana Lazovic, Milica Stankovic from Serbia, seems to be the most radical architectural concept out there right now, correct me if I'm wrong:

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This quite beautiful eco-friendly structure was designed by Indian architect Vikas Pawar for the city of Noida - more info

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Another eVolo concept worthy of mention is the Flat Tower, by Yoann Mescam, Paul-Eric Schirr-Bonnans, Xavier Schirr-Bonnans, France:


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Here is 1 Dubai: at 850 meters, it consists of three linked towers, clad in "mosaic-like glass and aluminum-mesh cladding" - designed by Adrian Smith & Gordon Gill:

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Among most elegant proposed skyscrapers we'll have to mention yet another colossal concept for Dubai (featuring beautiful spiral shape) - Dubai City Tower, 2500 meters high:
Glorious Retro-Future Urbanism from the Golden Age of SF
(left image via; right image: Popular Science, 1933)
"Metropolis" poster by Boris Bilinsky from 1926 and a street view:


Frank R. Paul's vision of a mighty city from "Amazing Stories", 1928:

Note the "slides" cascading down the building! This picture is from 1934:

Moving armchair transportation system, 1939:

Certainly not for those seeking some exercise and weight loss.