The Sahara desert may not be the most obvious location to build a futuristic ‘vertical city,’ but French architects OXO’s latest design aims to kick sand in the face of such a tough challenge.

Comprising eight per cent of the world’s land area, the Sahara is expanding south, forcing many of the four million people who live there to migrate – and so a sustainable city is proposed as a possible solution.

OXO’s concept for a 450m (1,476ft) high mixed-use tower would overcome the extreme desert conditions by utilising renewable resources such as rainwater collection, solar power and geothermal energy to ensure self-sufficiency. A central tower inside the structure would act as a vertical garden, while the building would also incorporate shades and natural ventilation to control the temperature.

The tower’s range is equally ambitious, with a meteorological observatory and a museum of the desert featured, alongside a hotel, panoramic restaurant, shops, housing and offices. Sports facilities and a swimming pool would also be included, and the tower would take up a surface area of 780,000sq m (8,395,850sq ft).

“This is not a tower, it’s a vertical city that is fully autonomous, energy self-efficient and has a vertical farm inside,” explained OXO. “It forms a landmark in the desert and creates a new mode of life by transforming the extreme characteristics of its climate sources into energy and freshness.”

French-Moroccan architect Manal Rachdi is the partner in charge of the project at OXO, which has teamed up with Paris-based Nicolas Laisne Associes to create the designs.

While conceptual at this stage and therefore not commissioned, the team believe work could begin on the project in 2025, with construction phased over 50 years.

The Sahara desert is in fact only the third largest desert in the world, behind Antarctica and the Arctic, and while the hottest temperature ever recorded is 58ºC (136ºF), night-time temperatures can fall to freezing and below in winter months.