This place results from the falling of the hill's central part while only the extreme lateral parts remain visible. Those parts have holes that are vestiges of the cave that once existed there.

A river that is also known as Ega river. It starts in the municipality of Ansião and flows to the Mondego river. It crosses th ruins of the roman town of Conimbriga along a canyon. The upper part of the river has no water during a large part of the year.