Why The Line

Cities today are mostly rooms in (home/office/store) units in buildings separated by roads. Besides roads, cities provide city services like power, water, sewage, and telecom. Buildings channel these services to units and add more like lights, air/heat, security, and elevators. Units are managed by particular orgs, who may add further local services like receptionists and IT, while people and small groups have their own rooms, over which they have some discretion.

Humans are more productive and engaged when we can interact with more others faster and more easily. The main way we achieve that today is via many adjacent tall buildings with supporting mass transit. But few buildings are very tall, and those roads take up much of the area, while remaining a bottleneck of movement. So for a long time another possibility has captured many imaginations: megastructures, such as this from Blade Runner:

Here more units could be spatially closer, and reached faster via many-level transit. An extreme version of this ideal is elaborated in my book The Age of Em. And this ideal was partly achieved in Hong Kong’s Kowloon walled city slum, destroyed in 1994:

While megastructures are popular among architects and in science fiction, ordinary folks are wary of them. Plausibly due to a combination of (A) each person seeing less sun, nature, or big views, (B) big clear inequalities (e.g., height and views), and (C) a dislike of feeling controlled. The cleaner the lines of an overall structure, the less choice any one person or org can have re their local appearance.

So we tend to instead idealize structures with a lot of haphazard greenery, little overt inequality, and buildings small and separated enough for each person to get lots of sun and views. Such as:

But alas, these can’t achieve megastructure-level densities.

This is the context in which I’d like you to consider The Line, a trillion dollar megastructure city now under construction in Saudi Arabia. It is to be 200m wide, 500m tall, 170km long, and host 9 million residents. This is a view of one end:

And this is a sample inside view:

If you search for The Line online you will mostly see pro stuff by its leaders and contractors, vaguely non-committal stuff by the prestigious architects paid to sketch concepts for it, and strong criticism from most everyone else. (Manifold markets say there’s over a 50% chance the project will be abandoned by 2028.) For example, many complain that its linear design induces higher internal travel costs than if the same height buildings were instead shaped into a filled-in circle of diameter 6.6km. Oh and its pretty hard to just start a new city. All of which are true.

But they miss the key point. The Line isn’t trying to make a max-dense megastructure, it is trying to make a record-dense megastructure people would actually choose, by avoiding the usual megastructure bad vibes.

So they max out its height (only 11 buildings in the world are now taller) and the fraction of it with big views of sun, sky, and nature. They design it to be zero emission, 100% renewable energy, with no cars, and on the outside try to make it look clean and in harmony with nature. On the inside they try to make make it look egalitarian, green, bright, lively, and varied. No top visually dominates the rest, and individuals express individuality. Its marketing is mostly prestigious folks talking good feels, not engineers talking design tradeoffs.

On reflection, I think they are roughly right. While megastructures could unlock enormous value, bad vibes are in fact their main obstacle, so The Line is right to do all it can to gain good vibes for a megastructure, and this linear design does seem to work well there. (Yes, Saudi Arabia gives many bad vibes, but they can’t change that.)

Of course the project faces many risks. They might screw up their design re transport, light, climate, dust, earthquakes, or governance. They might have cost-overruns and lose funding. (Though strong backing by Mohammed bin Salman, Crown Prince of Saudi Arabia since 2017, seems promising.) Or they might find they can only recruit limited capacity to build very tall, and be stuck growing The Line slowly.

Note that inside views offered tend to show light coming straight down from above, which happens only rarely. On other days, the inside will be a dark canyon unless there are many big light openings in the south wall.

Note also that when the main line gets too long or runs out of room, little will prevent the city from adding perpendicular lines out from the main line, converting the look of this to more like an ordinary city. And early on they will probably extend green parks out on either side.

My guess is that the hardest part of this project will setting the right level of freedom for units to choose what they do where, and designing new interfaces for units to fit into The Line’s combined building/city infrastructure. Today, orgs have a lot of experience making new schools, hospitals, stores, apartments, etc. by starting with on empty plots of land. But in The Line they must instead adapt such plans to fit into the spatial slots and infrastructure capacities on offer there. I hope they figure out something good.

If it takes twenty years to prove this concept, I fear it will be too late by then to inspire other new cities along the same lines. After all, soon after then world population will peak, and as buildings are durable there should be far less demand then for new buildings or cities during a declining economy.