A beautiful panorama from the roof of the Grande Arche de la Defense.

A view from the roof of the Grande Arche de la Defense.

The helipad on the roof of the Grande Arche de la Defense.

All of this triumphal arch was sculpted by Eugène-Louis Lequesne.

On the roof of the Grande Arche at La Defense, Puteaux.

Many collapses in this part of the quarry with beautiful arches.

Large arches and support beams in the quarry Keppler.

Quarries of Herblay are over 14km wide and some hundreds of meters deep, on hillsides along the Seine.

In 1776, the exploitation of new underground quarries in Paris was forbidden. People had to take the stone elsewhere. It is for this reason that the quarry was known as "Imperial quarry" or "Quarry of the city of Paris". They built many monuments in Paris with this stone because it was high quality (the famous Royal stone).

Among the monuments built, there was The Pantheon of Paris, Department of Marine Place de la Concorde, the Gare de l'Est, the mint as well as many statues at Versailles.

The network's quarries has been excessively exploited in Herblay. The ceiling is fragile and the walls separating the tunnels are very thin. To reinforce the quarry, they have added many pillars and reinforcement structures.

Later, like many underground quarries, they served to mushroom plantation in the 1980s. The workers have dug additional corridors between small quarries networks.

A few years later and they were gradually abandoned. The latest mushroom plantation closed in 1995.

Since 2003, the association "Herblay heritage" has undertaken to make public visits to the part of the "English entry" with the famous double-arched vault and pretty ponds.

Quarry of Triel sur Seine

In 1870, France is partly occupied by Prussian armies. Following this defeat, it sets up the Sere de Rivières system that allows for the construction of fortifications to defend Paris. It is in this context that the High Fort Buc was built. Work began in August 1874 and ended in 1880.

The Fort High Buc is part of an ensemble of two forts, Fort Villeras located in Saclay and Fort High Buc, and smaller peripheral structures.

From 1979 to 1995, the arms company Thomson amends hard to build a missile factory. The book is sometimes used by the national police, to conduct trainings in combat.

In 2010, the city has opened a contest for best restoration project site.