The Saudi ‘line’: urban marvel or nightmare?

In October, the excavation work for the super construction project began. While some see it as a perfect example of a green urban area, others dismiss it as a publicity stunt. Now, scientists from the Complexity Science Hub explain why Line It should not serve as a model for the cities of tomorrow.

“It’s the embodiment of a dream, of starting from scratch and completely rethinking the city,” says Rafael Brito-Curiel, who researches cities at the Complexity Science Hub. Line It is planned to be a city built out of nothing in the desert. It is slated to consist of two huge uninterrupted rows of skyscrapers, with living space in between. Its length is 170 kilometers. 200 meters wide. Its height is 500 meters, which is higher than any building in Europe, Africa and Latin America. Head straight from the Red Sea to the east.

Ten times denser than Manhattan

Nine million people are expected to live there – more than any other city in Saudi Arabia. This translates to a population density of 265,000 people per square kilometer – ten times the density of Manhattan and four times that of inland Manila, which is currently estimated to be the densest metropolitan area on Earth. “How you can attract so many people in a medium-sized country at all has not yet been noticed,” Brito Curiel points out.

At 500 metres, the line will be taller than any building in Europe, Africa and Latin America – and will exceed 170 kilometres. Source: Center for Complexity Sciences/Prieto-Curiel

Sixty minutes to the flight

Other questions arise regarding mobility. “The line is the city’s least efficient form,” Brito-Curiel says. “There is a reason that there are 50,000 cities in humanity, and they are all more or less round,” he asserts.

If we choose two people at random LineBetween them, on average, 57 kilometers. In Johannesburg, which is 50 times larger, two random people are just 33 kilometers apart. Assuming a walking distance of 1 km, only 1.2% of the population are within walking distance of each other. This hinders active movement, so people will rely on public transportation.

The backbone of public transportation is planned to be a high-speed rail system. “For everyone to be within walking distance of a station, there must be at least 86 stations,” explains Daniel Condor, researcher at CSH. As a result, trains spend a lot of time in stations and will not be able to reach high travel speeds between any two stations. According to the researchers, the journey is expected to take an average of 60 minutes, and at least 47% of the population will travel longer. Even with the extra fast lines, the winnings are limited by the additional conversions necessary. The result is that people will be traveling longer compared to other major cities, such as Seoul, where 25 million people commute for less than 50 minutes.

a| The location of the line in the Kingdom of Saudi Arabia. b | Expected travel time (vertical) by number of stations (horizontal). c | The largest cities in Saudi Arabia, including the planned population of The Line. Source: Center for Complexity Sciences/Prieto-Curiel

A city is more than just a neighborhood

Research shows that people want to spend a limited amount of time commuting, so efficient transportation plays a major role in the success of cities. But can these trips through the city be avoided because the high density allows everything (jobs, shopping, utilities, etc.) to be available locally? “Cities are more than a collection of semi-isolated 15-minute blocks right next to each other. What distinguishes a city from smaller settlements is not just its size, but additional opportunities outside the immediate neighborhood – such as concerts or an expanded job search. “For this reason, we need to consider transportation at the city level,” Condor explains.

Why not “the circle”?

If you take Line and make it Circle With a radius of 3.3 km, the distance between any two people would be just 2.9 km, and 24% of the population would be within walking distance of each other. Most modes of transportation can be active (walking, cycling, or similar), making a high-speed rail system unnecessary. instead, Circle It can allow good communication even at low densities, avoiding the need for tall buildings.

Is there something positive?

“This project gets people to discuss urban forms, which is very important because cities, especially in Africa, are growing,” says Brito-Curiel. Historically, cities often grew in organic ways, while planned cities often did not live up to expectations; Thus, there is a need for more public participation in urban design on a human level.

In addition, emphasis is placed on sustainability in many aspects of the project. For example, there will be no cars for distances of less than five minutes on foot. This not only saves a lot of space in terms of infrastructure and parking, but also reduces the number of cars. Moreover, all energy will be produced with zero carbon emissions. But what is not taken into account here is the construction of skyscrapers, which requires a lot of materials and energy.

“In general, it stands to reason that other considerations might have played a role in choosing this unique format, such as branding or creating engaging videos on social media. However, it is important to understand the consequences, especially if Line It is treated as a showcase for modern construction and urban planning technologies”, says Brito Curiel.

Reference: “Arguments for Building the Circle, Not the Line, in Saudi Arabia,” by Rafael Brito-Curiel and Daniel Condor, 19 June 2023, Available here. npj urban sustainability.
DOI: 10.1038/s42949-023-00115-y