Saclay (France) (AFP)

Behind gates and barbed wire, 6,000 researchers, a pond, woods and superb buildings by the architect Auguste Perret: the Atomic Energy Commission (CEA) opens Saturday the doors of its ultra-secure center in the Paris suburbs.

25 km from Paris, between the wheat fields and the works of the future campus of Paris-Saclay, the entrance of the CEA center has the airs of border post. Here, it is nuclear. Access is forbidden to the public.

But Saturday, for the sake of openness, the center will welcome some visitors, previously registered, on the occasion of Heritage Days.

Today, 8 nuclear facilities are located in this center. "Permanent or dismantling facilities, all dedicated to research.There is no production activity here," says center director Michel Bedoucha.

After "some access procedures", visitors discover 220 hectares dedicated to research, 33 km of roads, perspectives to the Versailles and a magnificent architectural heritage.

"The atomic center is the last great work of architecture and urbanism Auguste Perret," says Ana Bela De Araujo, architect author of the book "The city of the atom".

Chosen to build this "showcase of French research", this specialist in concrete, great architect of the reconstruction of Le Havre-classified World Heritage by Unesco- or the Palais d'Iena in Paris, has designed plans in 4 month.

- "Absolute urgency" -

"After the war, scientific research in nuclear physics is an absolute emergency for France, both for the energy independence it provides but also to bring the country back to the highest level in the world. , France must have it too, "says Ana Bela De Araujo.

As a result, Auguste Perret conceives a heterogeneous city where representative buildings meet (Marshal Tito and Queen Elizabeth of England have notably made the trip) and utilitarian, industrial sites.

The further you get from the center and its "noble" buildings (like the monumental canteen), the more cars and pedestrians are scarce, the more the sounds fade, the more the architecture becomes industrial.

Visitors will discover huge buildings such as the "test hall" with its 1.200 m2 room, lit by 13 m high windows. Long, like the "Chambord" which housed the EL2 battery, a nuclear reactor. High as the "Van de Graaf" which hosted a linear accelerator.

And the architect also rubbed shoulders with the "art of camouflage", with the "small pink concrete palace" looking like a primary school that housed the cyclotron, a circular particle accelerator commissioned in 1953. basements to walls one to two meters thick nowadays serve as backdrops for retro-futuristic films ...

Since its conception, the "City of the atom" has continued to grow, exceeding its initial role, scientific-military-industrial.

Today, nuclear physicists are meeting climate and environmental specialists (some of them are part of the Intergovernmental Panel on Climate Change, the IPCC), life sciences, health, environmental science and technology. Universe, from CEA, CNRS, Inserm ... In total, 8,500 people work on the center.

© 2019 AFP