At this stage of the journey, you tread on soil that hides ancient secrets. The region between Mira de Aire and Orçário is the gateway to Portugal's fascinating underground world. Here, geology takes centre stage, with the monumental Mira de Aire and Santo António caves standing out. As you walk on the surface, among the limestone carved by rain and wind, imagine the galleries, lakes and stalactites that water has patiently sculpted in the dark, creating true natural palaces that are well worth a visit.

But Mira de Aire also offers another kind of depth, a historical one. The urban and peri-urban landscape reveals the heritage of a town that was once a driving force in the textile industry. Old structures and chimneys dot the horizon, reminiscent of times of looms and workers. The route continues along rural trails that wind up the hillside, where Mediterranean flora, kermes oak, arbutus and aromatic plants perfume the air, creating a vibrant contrast with the apparent aridity of the rock.

This stage is a living lesson in geography and biology. As you cross the Alvados area, you enter a territory of great ecological wealth, where the local Interpretation Centre serves as a beacon of knowledge. In the wetter valleys, the vegetation becomes denser and the holm oaks create tunnels of refreshing shade.

Between Orçário and Alcaria, the landscape opens up into breathtaking scenery, dominated by the Polje de Alvados e Minde and, above all, by the majestic Fórnea. This natural amphitheatre, a perfect bowl-shaped depression, is one of the most photogenic spots in the entire Natural Park. The Fórnea Viewpoint offers the ideal vantage point from which to understand the force of erosion and the scale of geological time.

Human presence blends into this setting, with villages maintaining a layout that respects the mountain, with houses that seem to spring from the rock itself. Here you can feel a perfect harmony between nature and mountain agriculture. In the vast mosaic of land marked out by dry stone walls, it is common to find herds of cows grazing freely in these high-altitude “corrals”, composing a bucolic picture where the silence is broken only by birdsong and the wind in the ridges.

At this stage of the journey, nature serves as a backdrop to engineering and collective memory. The connection between Alcaria and the Bezerra Eco-Trail is a true journey through time, where each step echoes centuries of human presence. The highlight is the monumental Roman Road of Alqueidão da Serra. Here, you walk on the same flagstones that served the Empire, and you can still see and feel the deep grooves left by the wheels of carts two millennia ago, an indelible mark of ancient trade routes.

The surrounding landscape, particularly in the Covão de Oles and Casais dos Vales area, is a living example of popular architecture. You are accompanied by the geometry of dry stone walls and “chousos”, which divide the land and demonstrate the local people's mastery in shaping stone for agriculture.

At the heart of this stage stands the majestic Porto de Mós Castle. With its palatial design and unmistakable green-domed towers, this monument watches over the Lena River valley and invites you to make a mandatory stop. The village also offers the Municipal Museum, which houses treasures ranging from prehistoric fossils to local ethnography. It is a stage where the ruggedness of the mountains merges with the nobility of history, offering a rich cultural experience in the middle of your walk.

The section connecting the Ecopista area to Arrimal transports you to the industrial history of the mountain. Much of this route follows the bed of the old mining railway line, the Ecopista da Bezerra. This is where the wagons loaded with coal extracted from the bowels of the mountains used to pass. Today, it is a spectacular panoramic balcony, suspended halfway up the hillside, offering unobstructed views over the valleys and allowing you to observe the entrances to the old mines, evidence of a hard working life.

You are in the heart of the Serra dos Candeeiros, a land of shepherds. It is not uncommon to encounter flocks grazing freely, keeping the landscape open and the cheese-making tradition alive. As you approach Arrimal, the hardness of the rock gives way to the serenity of the water. The Arrimal lagoons appear like an oasis, a mirror of water surrounded by greenery, meeting places for the community and an ideal resting spot.