Access to Adraga beach from:

- Sintra (± 14 km) – N247 and praia da Adraga street.

GPS: 38.8005556,-9.4883333

Take good care of yourself! Do not approach the seashore especially with a storm. Be careful of existing cracks. Don’t risk it! ICNF, I.P. don’t take responsibility for any accident occurred.

In this zone there are volcanic rocks in the middle of the limestones, having different resistance to erosion, caused by the rains, but, above all, by the sea. Due to this, a set of cavities (caves) were formed.

Near vertical cliffs overlooking Adraga beach are mainly made up calcareous layers dating back to the Upper Jurassic era, around 150 million years old. The numerous large rocks set apart in the sea attest the rapid erosion of this coastal area.

Along the cliffs are several faults and eruptive seams.

The corrosive action of rainwater on these chalky layers, especially along fracture lines, has given rise to a system of deep vertical fissures and caves, the most spectacular is Fojo dos Morcegos (bat pit).

Alvidar stone is another interesting geological accident. It is a layer of crystalline Jurassic limestone that has remained almost vertical, having being overheated and squeezed more than 80 million years ago with the ascent of Sintra eruptive massif.

The cliffs are colonized sporadically by sea-fennel, samphire and several lavanders. Many birds nest here thanks to the protection from predators.

An air of mystery has shrouded this area: the alleged pagan rituals; the roman legend of the presence of a triton and a Nereid at the bottom of Fojo dos Morcegos and the existence of an ancient or Moors court at Alvidrar stone where those accused of crimes were thrown into the sea.