Saudi Arabia has unveiled its ambitious plans to build the world’s largest structure.
The structure, known as The Line, will be comprised of two glass reflective buildings measuring up to 488 metres (1,600 feet) high, running parallel for 170 kilometres across coastal, mountain and desert terrain, Al Jazeera reports.
The two buildings will be connected via walkways, and a high-speed train will run underneath them. The structure is expected to cost a whopping $1 trillion upon completion, and is projected to house five million people who will be able to travel end-to-end in 20 minutes.

The plans include concept designs such as integrated vertical farming, a marina for yachts, and a sports stadium built up to 305 metres (1,000 feet) above ground.
The structure is the epicentre of Crown Prince and de facto ruler Mohammed bin Salman’s zero-carbon smart city project called Neom, which will cost another $500bn to build and is the size of the US state of Massachusetts.

Neom is owned by Saudi Arabia’s sovereign-wealth fund and is part of a framework called Saudi Vision 2030, a plan that seeks to diversify Saudi Arabia’s economy and reduce its dependence on oil.
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“At The Line’s launch last year, we committed to a civilizational revolution that puts humans first based on a radical change in urban planning,” said Saudi Arabia’s crown prince Mohammed bin Salman.
“The designs revealed today for the city’s vertically layered communities will challenge the traditional flat, horizontal cities and create a model for nature preservation and enhanced human livability,” he continued.
“The Line will tackle the challenges facing humanity in urban life today and will shine a light on alternative ways to live.”

While the deadline to build Neom is 2030, the Wall Street Journal reported that an initial impact assessment of the Mirror Line produced in January 2021 said the development would have to be constructed in stages, and could take 50 years to complete.
The Mirror Line’s initial design is by the US-based Morphosis Architects, founded by Pritzker Architecture Prize winner Thom Mayne, and involves at least nine other design and engineering consultants.
Image credits: Morphosis Architects
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