In the quarries of the 16th in Paris, in the Palais de Chaillot. These quarries have been called "catacombs Trocadero" because a part was used in the Universal Exhibition of 1900 to show the public the geology of the basement. Height 55 feet 4 inches / 17 Metes 8693 (as printed on the wall)

We call these underground quarries "quarries of Chaillot". The size of these quarries was 12 acres originally, but now it remains only a small network of underground tunnels. At Expo 1900, we used a small portion of the underground galleries to present the work of mining and underground quarries. A prototype of the Channel Tunnel was also conducted.

A very steep slope that leads to the exploitation level of the underground quarry. Here the picture is taken at mid-height of the slope.

Quarries of Paris - The network located in the Val de Grace hospital.

Beside the stairs Mansart, whose name was chosen in reference to the architect François Mansart, author of many works of consolidation in the hospital of Val de Grace.

A plate shows the depth of the underground quarry with great precision: Height 58 feet 6 inches or 18 meters 9969.

The whole cathedral is reinforced by these metal rods. Locally, the buttresses have pillars of sites to prevent movement. Height Gothic heart of 48.5 m world record!

The limestone quarry of Chanaz is a smaller operating on three levels. The ceiling height is between 5 and 10m. Sometimes, holes in the floor let you see underground levels.

The network size is almost 4km developed. It was exploited from 1860 to the end of the Second World War to make cement. Portions was reused as mushroom farm thereafter (row crops and cultures in bags).

In this photo taken at the highest level, we see the intermediate level, row crop bottom right and even two holes overlooking the lower level. This is the most impressive part of the network with large volumes!

The height of the Loyasse was built between 1836 and 1840. Here, within a stronghold in the north of the structure.

Hey it's Tim from glauque-land! A very nice guy!

Pan on the heights of the cathedral of Chartres.

Around the Garnier opera, all buildings are height limited. So the view from this crane is very unique!