The Line, Explained: What Saudi Arabia Is Actually Trying to Build at NEOM

One image has shaped global perceptions of modern Saudi Arabia more than any other: the render of The Line. Two parallel mirrored walls running across the desert, an entire city sealed between them. It's the flagship of NEOM, the northwest region pitched as a clean-sheet experiment in how people live and work. It's also the most heavily doubted piece of Vision 2030. To see why, you have to separate the pitch from the physics.

What the proposal claims

As published, The Line would be a linear city roughly 170 kilometres long, about 200 metres wide, and rising some 500 metres — taller than most skyscrapers — clad in mirrored glass. The promise is a city with no cars and no roads, where everything you need sits within a five-minute walk and longer trips run on high-speed rail beneath the structure. Renewable energy, vertical layering of homes, offices and parks, and an AI-managed environment round out the vision.

The stated logic is environmental and spatial: by going linear and vertical rather than sprawling, NEOM's planners argue, you preserve surrounding nature, cut commuting, and concentrate infrastructure. Whether that logic survives contact with construction is the open question.

Where the engineering gets hard

Building two continuous mirrored walls hundreds of metres high across desert terrain is unlike anything attempted at scale. Engineers have raised concerns ranging from the structural loads and thermal behaviour of a sealed mirrored corridor to wind, sand, and the sheer logistics of a worksite stretching across a region. Mirrored exteriors also raise questions about bird collisions and glare that planners say they are addressing.

Then there is the human side. A linear city is, by definition, narrow, which makes movement along its length the central design problem. Critics note that a five-minute-walk promise and a 170-kilometre length are in tension unless the population is sliced into self-contained modules connected by very fast transit.

The reported scaling-back

By the time most readers encounter The Line, the news has shifted from renders to reality checks. Multiple reports have suggested that near-term ambitions have been trimmed — that the stretch expected to be complete by 2030 may be a small fraction of the full length, housing far fewer residents than the headline figures of nine million once implied. NEOM officials have generally framed these as phasing decisions rather than abandonment.

It is worth holding two ideas at once. The full 170-kilometre mirrored city remains an ambition, not a delivered fact, and should be read that way. At the same time, very real construction — earthworks, excavation, worker housing, and supporting infrastructure — is underway, and other parts of NEOM, including the Oxagon industrial zone and the Trojena mountain resort, are advancing on their own timelines.

The honest summary, for the curious visitor: NEOM is at once the boldest and the most contested item in Vision 2030. The Line might end up a partial city, a prototype, or something in between. What it already is, fairly or not, is the symbol the whole plan gets judged against.