The mountain bike stage from Puente de los Fierros (Lena) to Caborana (Aller) is one of the most demanding stages on the route, covering 37 kilometres with a total elevation gain of approximately 1,500 metres. The route mostly runs along dirt tracks, although there are also some mountain paths and trails that make the stage challenging. It is ideal for cyclists with a good level of physical fitness and experience in mountain terrain.
From Puente de los Fierros, the route starts with a steady climb through a landscape of great natural beauty: dense woods, meadows and impressive views of the mountains of Asturias. As you gain altitude, the dirt tracks wind through valleys and hillsides, making for a technical itinerary with some steep slopes that test your resistance. The downhill sections also need to be negotiated carefully, as there are stony stretches that require good riding skills.
The final section enters the municipality of Aller, where the landscape combines high mountain peaks and green valleys to create a spectacular end to this challenging stage. Once in Caborana, riders can recharge their batteries and enjoy the charm of this village before continuing along the route.

The mountain bike stage between Caborana (Aller) and Puente de los Fierros (Lena) is one of the most challenging on the route, covering 37 kilometres with a total elevation gain of approximately 1,700 metres. Most of the route runs along dirt tracks, with a few sections of mountain paths and trails that add some technical difficulty. Due to its demanding profile and long climbs, the stage is rated as ‘very demanding’, so it is recommended for cyclists with experience in mountain terrain.

After leaving Caborana, the route starts with a long and demanding climb. It crosses the impressive scenery of Asturias, featuring leafy woods, high-mountain pastures and hillsides with spectacular views. The steep slopes and the length of the climb test riders’ resistance, who need to dose their efforts in this section. As you gain height, the route alternates between more open areas and technical downhill sections in which the surface may present some irregularities, requiring good control and riding skills.

The final stretch descends towards Puente de los Fierros at the end of an intense day on the bike among spectacular landscapes. After this tiring challenge, riders deserve a rest in this highly picturesque hamlet.