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Spectacular sunset in Gavà, in the Baix Llobregat, with this perspective of the beautiful twilight rays projecting over the Garraf massif, as we see in this snapshot in Las Fotos de los Lectores de La Vanguardia.

Crepuscular rays, in atmospheric optics, are rays of sunlight that appear to radiate from a single point in the sky. We see in these images how they are projected onto the massif.

These rays flow through openings in clouds (especially stratocumulus) or between other objects. They are columns of sunlit air separated by dark regions of cloud shadow.

The name comes from its frequent appearances during twilight hours (sunrise and sunset), when the contrasts between light and darkness are the most obvious. Not in vain does crepuscular come from the Latin word crepusculum, which means “twilight.”

The Garraf massif rises in the Catalan Coastal Mountain Range. It occupies a triangular area between the Llobregat valley, the Penedès depression and the Mediterranean. It forms a group of low mountains. Orographically it goes from sea level to 593 meters from the top of Morella.

The Garraf massif loses height towards the west and disappears near Vendrell, where the coastal depression is limited by the sea. The mountains are limestone with many chasms and caves. And the palmetto is an endemic species in this area.