Access coming from:

- Alcanena (± 6.7 km) – N365 to Moitas Vendas.

- Porto de Mós (± 24.8 km) – N243 to Moitas Venda.

The best place to see this depression is on the main road connecting Moitas Vendas to Serra de Sto. António (Fonte street / António Galveias Dias street).

On the basis of the reverse of Costa de Minde and less than 2 km north of the geologic accident which is the thrust of Estremenho Limestone Massif on the tertiary basin of Tagus River (Arrife’s thrust), on the southern side of Sto. António plateau, Covão do Feto is a closed karst depression, more or less round and with a flattened bottom covered with clay sediments with agricultural and grazing potential. In the edges of the depression is the village with the same name.

With a depth of about 40 m from the top of the gentle slopes, the depression has approximately 1.2 km long by 1 km wide, appearing to show a structural control following the exposure of the great existing faults in the region with parallel orientation to Arrife’s fault.

Its origin may be related to a waterline valley served as the main collector to drain the eastern plateau sector to the Tagus basin in Covão do Feto region and have evolved into a blind valley when the massif rise. After that the waterline infiltrate in depth, but the proximity to the saturation karst area must have conditioned the depression appearance, with periodic flooding being responsible for flattening the bottom.

Blind valley – a valley formed by a watercourse that ends suddenly on the point where the stream/river disappears underground.

Depression – landform sunken or depressed below the surrounding area.

Doline (also known as sinkhole) - a closed surface depression draining underground in karst landscape. Dolines are usually "bowl-shaped" and can have only a few or many hundreds of meters in diameter.

Karst - A distinctive topography that indicates dissolution of underlying soluble rocks by surface or ground water in areas of easily soluble rocks. Characterized by caves, underground drainage and sinkholes.

Polje – limestone relief form consisting of an elongated and long depression generally flat bottom. Often it has a very steep slope corresponding to a fault. In rainy periods it often becomes a temporary pond.

Terra rossa – Italian expression meaning “red soil”. The terra rossa soil is heavy and clay-rich (silty-clay to clayey) soil, strongly reddish, developed on limestone or dolomite.

Thrust - formed by horizontal compressive stresses and so cause shortening of the crust. Because the hangingwall moves up relative to the footwall, most of these faults place older rocks over younger ones.