Fórnea

An impressive natural amphitheatre, carved out of the marl and limestone formations of the Lower and Middle Jurassic. This reculée, or pronounced indentation, took shape as a result of regressive erosion caused by the Fórnea creek, the action of rainfall, spring waters and during colder climatic periods – from which we have inherited the gravels and cryoclast deposits. Its sharp relief, about 250 metres high and 500 metres in diameter, can be viewed from above, from Chão das Pias, or admired from the bottom, in Alcaria. On the slopes of the amphitheatre, the balconies, or steps, tell the details of its geological history. In the region, which was once an epicontinental sea, there are plenty of fossils of ammonites, belemnites, brachiopods and bivalves. To the north of Fórnea, on the limestone slab of Barranco do Zambujal formation, we find the Ammonites Trail, where fossils of this marine animal, an inhabitant of the Jurassic seas, have been imprinted. At the top of Fórnea, in Chão das Pias, the wind almost carries us away as we enjoy the vast horizon. On the limestones, Mediterranean vegetation is scattered with kermes oaks (Quercus coccifera L.) and aromatic herbs. The landscape follows along stony escarpments which, at the time of the heaviest rainfall, form the waterfalls of Fórnea creek, in the direction of Alcaria. It is part of the PR4 pedestrian route with a variant that gives access to Cova da Velha Cave, the main seasonal spring in this formation.