The Sirenians Trail
The Sirenians Trail

The Sirenians Trail

A lookout, a viewpoint
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And strange marine mammals called the sirenians inhabited our lands...

40million years ago, the col des Lèques was under the sea. In this warm sea lived peaceful marine mammals: sirenians (ancestors of the current dugongs and manatees). In a unique place in the world, set up by the Haute Provence geological reserve, you will discover remains from 35million years ago.

6 points of interest

  • Patrimony and history

    The pass of Lèques

    The "neighborhood" called Lèques situated to the north of pass of Lèques evokes the name of these thrush traps, consisting of two flat stones, that allowed to trap the birds at that time (a completely prohibited practice today). A few juniper berries, thrushes’ favorite candy in winter, were placed between the sticks. The bird had to move the sticks to peck at grains, and the vertical stone fell and knocked it.

  • Panorama

    Roc de Castellane

    Overlooking the town from its 184m straight and steep cliffs, the top of the Roc is decorated with a chapel topped by a statue of the Virgin and Child. Majestic, strong and anchored since the dawn of time, it looks like the relic of a surrealist dungeon, left there by improbable and fantastic creatures.

  • Geology

    The valley of fossil mermaids

    Fossils less than 1% of living things are found fossilized, which goes to show that fossilization is somewhat “miraculous”. It is the transformation of the remains of an organism and its conservation in rocks. Obviously, the mineralized portions (skeletons, shells, etc.) are best preserved. But wood and fingerprints, traces of activities, could also be preserved, thus providing valuable information.

  • Geology


    Fossils relate us about the history of life. They have allowed the birth of the theory of evolution by showing us the existence of now extinct animals. In our region, ammonites are a good example. They disappeared 65 million years ago after having populated all the seas of the globe during the Mesozoic era.

  • Geology

    The fossil valley

    Water sometimes flows into the ravine. In its work of erosion, it gradually reveals the relief shaped for the first time more than forty million years ago. On the right bank, you can see a gray limestone massif dated back to 140 million years (Jurassic). On the left bank of the marls and yellowish sandstone limestone, dating back to 40 million years.

  • Geology

    the Sirenia

    If sirenians the ravine of Tabori, who lived in the sea, are now at nearly 1,000 meters above sea level, it is not because of a sudden drop in the water level. The sediment accumulated at the bottom of the sea for millions of years are found upright and altitude when the Alps were raised.


From the car park at the Col des Lèques, take the path along the campsite. In 500m, follow the path and find a small pass and an intersection of marked trails.

1 - Go left and leave on the right the trail going up towards La Baume. Find a ruin by the relatively flat and shaded path. Pass by and then find a small footbridge. After crossing it, climb the trail with a few wooden steps under the pines. Cross the next valley and find a view of the Col des Lèques, the north face of Cadières de Brandis and the summits of Robion and Destourbes, dominating Castellane. Go down the path and go to the right in the direction of the valley where the sirenian fossil site is located.

2 - The same route is used for the return.

  • Departure : Col des Léques, Castellane
  • Arrival : Col des Léques, Castellane
  • Towns crossed : Castellane


Altimetric profile


avoid the heat of summer, bring a hat, water, and walking shoes. The first part of the route passes close to the pastures of the sheep in spring and autumn. The course may be slightly deviated in this area to avoid crossing the herd. Follow the markup. Keep dogs on a leash.

Information desks

House of the Verdon Regional Nature Park

Domaine de Valx, 04360 Moustiers-Sainte-Marie (0)4 92 74 68 00

House of the Verdon Regional Nature Park

Find out more

OTI Verdon Tourisme

Rue nationale, 04120 Castellane (0)4 92 83 61 14


« Limitons les déplacements en voiture, pensons aux transports en commun ! Prenez la ligne régionale BV1bis entre Riez et Castellane du 1er Juillet au 11 octobre. Depuis Riez, départ 8h35, retour 16h00. Depuis Castellane, départ à 7h30, retour 16h20 et 19h30. Retrouvez tous les horaires sur ».

Access and parking

8km from Castellane, take the RN85 towards Digne-les-Bains until Col des Lques.

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