Mirror Line: Saudi Arabia’s Neom to build the world’s longest skyscraper
Vertical city THE LINE NEOM revealed
The Line is a proposed smart linear city in Saudi Arabia in Neom, Tabuk, currently under construction, which is designed to have no cars, streets or carbon emissions. The 170-kilometre (110 mi) long city is part of Saudi Vision 2030 project, which Saudi Arabia claims will create 380,000 jobs and add $48 billion to the country’s GDP. The Line will be the first development in Neom, a planned $500 billion city. The city’s plans anticipate a population of 9 million.

The plan for The Line was announced on January 10, 2021, by Saudi Crown Prince Mohammed bin Salman in a presentation that was broadcast on state television. Upon completion, The Line will be 170 kilometres (110 mi) across, will preserve 95% of the nature within Neom, and is expected to have nine million residents. The Line’s plan consists of two mirrored buildings with an outdoor space in between, having a total width of 200 metres (660 ft) and a total height of 500 metres (1,600 ft). The city will be divided into nodes. All daily services are designed to be reachable within a 5-minute walk.

The city will also be powered entirely by renewable energy. The Line will consist of three layers, including one on the surface for pedestrians, one underground for infrastructure, and another underground for transportation. The transportation layer will include a high-speed rail system, which is claimed to allow people to go from one side of the city to the other side in 20 minutes when finished, reaching a speed of 512 km/h, which is faster than existing high-speed rail at the time of announcement. Artificial intelligence will monitor the city and use predictive and data models to figure out ways to improve daily life for citizens in The Line.

Estimated building cost is US$100–200 billion (400–700 billion SAR), with some estimates as high as $1 trillion. It is claimed by the Saudi government that it will create 380,000 jobs, spur economic diversification, and contribute 180 billion SAR (US$48 billion) to domestic GDP by 2030.
Initial earthwork began in October 2021, at which time its first residents were expected to move in during 2024. As of July 2022, the first phase of the project is scheduled to be completed in 2030.

Crown Prince Mohammed Bin Salman, also Chairman of the NEOM Board of Directors, released a statement and promotional video on July 25, 2022, which led to more widespread media coverage of the project. This also raised questions about the merits of the design and environmental issues, with critics concerned the project would create a “dystopian” and “artificial” facility that has already displaced the Huwaitat indigenous tribe and would impact the migration of birds and wildlife.