“A journey through space and time” aboard the GeoTrain

“There are petrified coconuts and shark teeth in Gan”

The project was launched last year on the initiative of the Pau geological association GéolVal and in collaboration with SNCF, local authorities and tourist offices. When the association heard about the renovation of the historic TER line between Pau and Canfranc, the association saw the opportunity to offer the public commented tours that tell the geological history of the Pyrenees. At the height of the morning, about fifty people had taken the TER.

This Tuesday, August 2, the apprentice geologist settles into a reserved seat at the front of the train. Annie Lacazedieu, with a hat on her head and a bag full of stones on her shoulder, welcomes the small group. “The zigzag railway corresponds to the geological landscape”, explains the chairman of the association, showing large schematic maps.

Geological expansion

“We are going on a trip through space and time. By observing the mountains, we see layers that correspond to periods. Like a pile of comics in a teenager’s room, you know? asks the guide to the two young boys next to the window.

Evan and Nathan are 13 years old. The first is passionate about science, the second was “dragged by force” by his mother, who sat across from him. Angélique Marchand has been waiting for this trip for three years and is considering joining the association GéolVal.


One must pay attention to the landscape to observe the rock formations mentioned by Annie Lacazedieu, president of the association GéolVal. “You’d almost need a panoramic roof to see better,” she says.

Anna PAUL/SOUTHWEST

Neophytes can be reassured, the tour is accessible to all. “Geology and me are zero”, assumes Élisabeth Lemasson, friend of Annie Lacazedieu, who participates for the first time in the excursion. “We go for walks with Annie, where she explains the geology, but sometimes we pick up, eh”, laughs the pensioner. She is satisfied with the very educational speech from the retired SVT academy inspector.

The unmarked TER was specifically chosen by SNCF for obvious reasons of visibility. Passing through Jurançon, we learn about the existence of a land with a strange name: pudding stone. The subject is not English cuisine, but the rocks visible at the foot of the vines.

A little further, the loose-eyed have the chance to see a petrified lava flow underwater

Underwater lava and glaciers

“These are solar heaters. The rocks absorb the heat of the day and redistribute it to the ground at night,” says the retired geologist. A little further on, the lynx are lucky enough to see a petrified lava flow underwater, which quickly emerges behind a bamboo grove.

Terminus at Bedous, in the heart of the mountains.  The rest of the stretch, which goes to the magnificent Canfranc station converted into a hotel, is being renovated.


Terminus at Bedous, in the heart of the mountains. The rest of the stretch, which goes to the magnificent Canfranc station converted into a hotel, is being renovated.

Anna PAUL/SOUTHWEST

Then, towards the Arudy plain, a cold moment in geological time, the train passes from the tropics to the glaciers. “There’s a glacial moraine here,” the guide begins, before being cut off by Evan’s exclamation. “I know what it is!”. He tells without fail how the plain was formed, after the melting of the glacier, which caused a flood, bearing the name of the breakup of the glacier.

Near Sarrance, TER is slow due to the collapse of a retaining wall on the railway viaduct last February. The opportunity to rest for Annie, and for the small group to observe the 150,000 tons of ballast between the rails, these little pink, gray and green stones that come from Scandinavia and the Basque Country.

Arriving at Bedous, the small group discovers fantastic fossils, like here an ammonite.


Arriving at Bedous, the small group discovers fantastic fossils, like here an ammonite.

Anna PAUL/SOUTHWEST

The arrival at Bedous offers a majestic scenography. Surrounded by mountains, the geologist pulls out rock samples, including one with a fossilized ammonite. The visit ends after the presentation of the association’s explanatory panels, which are found at each station and along the Trans-Pyrenees Geological Route. Travelers can return before the next TER and test the geological explanations in augmented reality by scanning a QR code on one of the GeolVal leaflets. Or go to the weeping rock, take an electric bike ride or even go tree climbing.

“Fabulous”, “brilliant”, “very interesting”, all participants are happy with the trip. “I don’t regret coming, we can ask questions, laugh. It’s a good time,” admits Nathan himself.

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