The Olhão municipality is mostly situated in the natural sub-region of the Barrocal (Lower Algarve), with areas of irregular relief covered with Mediterranean scrub, which make frontier in the south with large areas planted with dryland orchards (carob, almond, olive and fig trees). In the coastline, the municipality includes part of the whole lagoon and dune system which is the Natural Park of Ria Formosa. At the rear of this system, the landscape rises to the north, with slopes of great scenic interest, occupied by bushes.
The Barrocal (Lower Algarve) limestone relief is characterized by its diversity of shapes, which over time were caused by the different hardness of the rocks responsible for the differential erosion, combined with the tectonic ones.
The average altitude of this area of the Algarve is not very high, reaching a maximum height of 410 meters at Cerro of São Miguel. In the municipality of Olhão, the Barrocal (Lower Algarve) does not determine the characteristic broad plateau, but a succession of these ascending to Serra of Monte Figo, karst structural relief, composed by a more vigorous terrain. The predominantly west-east orientation of these surfaces, materializes a natural amphitheater facing the Ria, having as the horizon the sea, making of this territory a very special place.
The Ria Formosa Natural Park, located right in the algarvian Littoral, it's characterized by the smoothness of the relief and covers an area of low altitude, not exceeding the quota of 60 meters, predominantly altitudes of around 20-30 meters, corresponding to the terminal part of the amphitheater towards the sea, in which it's distributed the relief in this region. In the south, is bounded by a set of barrier islands of sandy shorelines, which separates it from the Atlantic Ocean.