This week, two architecture studios have announced concepts for structures over a mile high.

The first scheme, called The Mile, is from international design and innovation office Carlo Ratti Associati (CRA), who have proposed the world’s highest vertical park and observation deck.

Developed together with German engineering firm Schlaich Bergermann & Partner (SBP) and British digital design studio Atmos, The Mile would be the tallest man-made structure ever created – around twice the height of today’s tallest building, the Burj Khalifa in Dubai.

From base to apex, the structure would be covered by plants and greenery and inhabited by hundreds of animal species. It would be built using a lightweight structure, based on a structural, 20m-wide shaft, kept in compression and secured through a net of pre-stressed cables. Various orbiting capsules – equipped with open-air Virtual Reality screens – would elevate people to the summit.

“Imagine you take New York’s Central Park, turn it vertical, roll it and twirl it”, said Professor Carlo Ratti, founder of CRA and director of the MIT Senseable City Lab.

“Following the example of the 1972 Munich Olympic complex, engineered by Joerg Schlaich and Rudolf Bergermann, which pushed the boundaries of the possible and became a milestone in architectural history, the structural concept for The Mile is technically feasible because of its consequent and uncompromised light-weight approach”, said Boris Reyher, associate at SBP.

The proposals will be presented to the public at the forthcoming MIPIM real estate show in Cannes, France.

The second scheme, called Next Tokyo 2045, is by Kohn Pedersen Fox Associates and the Council on Tall Buildings and Urban Habitat, who've collaborated to visualise a new district in Tokyo in the year 2045, featuring a supertall megacity called Sky Mile Tower at its heart.

Next Tokyo 2045 would be located on a man-made archipelago which has already been earmarked for development. The Sky Mile Tower – at 420 storeys – would house 55,000 people and include leisure facilities such as gyms, shops, restaurants, hotels, libraries, sky lobbies and open-air terraces.

Low-elevation areas in the neighbourhood would be protected from natural disasters and rising sea levels by breakwater bars and operable floodgates.

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