Plans have been revealed for a 100-mile-long structure that is set to become the centrepiece of the ambitious Neom mega-development in Saudi Arabia.

Called The Line, the "horizontal city" will be 200m wide and built on a footprint of just 34sq km.

Designed to run on 100 per cent renewable energy The Line will eventually accommodate nine million people, with housing, parks and public spaces, retail and leisure facilities and a transport network.

Its reduced infrastructure footprint has been designed to create "never-before-seen efficiencies in city functions".

The Line will have an outer mirror facade, allowing it to blend with nature, while the interior will be built to create "extraordinary experiences and magical moments".

The unique design will also mean residents will have access to all facilities within a five-minute walk.

A high-speed rail system will transport people and goods from one end of the city to the other in 20 minutes.

The announcement of The Line's designs is a continuation of the Neom Company’s progress in the development of its flagship project, such as Oxagon – a reimagined manufacturing and innovation city; and Trojena, a global mountain tourism destination that will offer the Arabian Gulf’s first outdoor skiing venue.

Design and 'backbone infrastructure is being handled by AECOM, while Dezeen is reporting that Morphosis is thought to be responsible for the architecture.

A representative of the Neom Company said: "We're committed to a civilisational revolution that puts humans first, based on a radical change in urban planning.

"The designs revealed for The Line's vertically layered communities will challenge traditional flat, horizontal cities and create a model for nature preservation and enhanced human livability.

"The Line will tackle the challenges facing humanity in urban life today and will shine a light on alternative ways to live.

"We cannot ignore the livability and environmental crises facing our world’s cities, and Neom will be at the forefront of delivering new and imaginative solutions to address these issues.

"Neom is leading a team of the brightest minds in architecture, engineering and construction to make the idea of building upwards a reality.

"Neom will be a place for all people from across the globe to make their mark on the world in creative and innovative ways.

"It remains one of the most important projects of Saudi Vision 2030, and our commitment to delivering THE LINE on behalf of the nation remains resolute.”

Once complete, Neom is set to be 33 times the size of New York City, approaching the size of Belgium.