Even though there has been a considerable amount of building at Arcosonti, to me Hexahedron represents one of the most pure expressions of Paolo’s ideas. The design has always moved me. This is a habitat for a 100 thousand people. The structure is about 3,000 feet high - a human made mountain. It is composed of two offset, inverted, pyramids - simple forms that, because of their relationship to one another, create an amazing Armature that frames a great variety of spaces. This Armature - this mountain - would be encrusted with landscaping and inside and outside “lots” where “buildings” for various purposes would be built. The building would never end - The Armature providing services, context and unity, the encrustation of landscape and specific structures a rich, always changing diversity. I would love to build Hexahedron. I think that it would be one of the great works of all time.
It is important to IMAGINE - to think through - what amenities a structure like this would provide that are nearly impossible to accomplish any other way. For one, the ability to walk to and have access, within a few minutes, to any one (or grouping) of a 100,000 people. The traditional “flat” city cannot provide this and it fails to do so at great expense. Because of the shape, configuration and size of the structure, it creates both landscape and micro climate. A layered approach to the exposure to this weather can provide an almost endless variety of landscape contexts with a minimal amount of mechanical tempering. The design is essentially a cube on a bias configured with an offset that creates a large open park about 1,500 feet into the air. This is a way to get the best of the Medieval city [rbtfBook], combine it with the best of modern technology and create a new form. The STREET [rbtfBook], particularly, can find an expression here that we have not see in centuries. A great deal of the food required by the population would be grown in/on the building, as well as, upon the immediate ground landscape below the structure and that surrounding the structure. Major services and transportation is provided in the vertical supporting columns of Hexahedron with the heavy technology below ground under it. Access to the natural surrounding landscape is a matter of a few minutes for each citizen - a maximum of 700 steps and a vertical drop. The size of the population equals a comfortable political unit - a small “city-state” capable of diversity, “replacement” [rbtfBook] and self-rule. One could imagine how a city like this, with some kind of theme and basin-of-attraction would play out over a couple of hundred years.
Designing Hexahedron will not be easy - there are many habits to break. The mechanical engineering will be challenging. The structural and physical building aspects, while massive in scale, do not, in themselves, present huge challenges except for one aspect. Remote Arcologies will present transportation challenges (during the construction phase, which can take decades) while those close to existing cities will offer political and transitional (social as wells as technological) challenges. However, if you look at the annual expansion of a city like Calgary or Los Vegas is can be seen that the scale of localized Urban/suburban building is not inadequate to that necessary for the making of Hexahedron. It is just that these are two opposed design strategies and the existing system-in-place (from zoning, politics, economics, infrastructure, ownership, social conventions, and power-bases) is tuned to the creation of horizontal spread.