Forêt des Cèdres

One of the trails leads to the Portalas viewpoint. From here, you can enjoy a panoramic view of the Durance Valley, the Alpilles, the Sainte-Victoire, and the Étang de Berre. 200,000 years ago, the Durance was a river that flowed through the Lamanon threshold to the sea, creating its delta in the current location of the Crau plain.

In the foreground, you’ll see the wild, narrow valleys of the Petit Luberon.

The structure of the area is that of an anticline, an arch-shaped fold, with the northern and southern flanks (the summit plateau and the Craus of Saint Phalès and Mayorques) composed of white, hard limestone that forms cliff lines. Its core, made of softer, clayey limestone, has been eroded away.

Walk 100 meters along the cliff to the right and discover the natural Portalas Arch below. On these rocky ridges, rainwater infiltrates and flows through. On the surface, this results in limestone carved with grooves and channels, known as lapiaz (or lapiés). At the base of the massif, this infiltrated water feeds perennial or temporary springs. The Portalas Arch is another example of how limestone dissolves and erodes through infiltration and erosion