Criticism of the megaproject has come from all angles. Concerns have been raised that climate change will make the region too hot to be habitable, that the single rail connection is vulnerable to security threats and that the technology envisioned for the city’s operations doesn’t yet exist.

Mathematicians in Austria ran the numbers and revealed that the linear concept would be inefficient, suggesting a circular design instead. The New York Times reported that The Line, despite its supposed 'small footprint', would displace a tribal community already living in its place.

Though seemingly unfathomable outside of a sci-fi novel, construction has started on the unconventional megacity. However, it’s already been significantly scaled down, with the 106-mile length reduced to just 1.5 miles (2.4km), and the population projections down to just 300,000 residents.

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