The Senda del Oso — a bike ride to remember
36 km of greenway over the old mining railway. No cars, no impossible climbs — just you, the river and the Asturian valleys.
car-free
for all levels
welcome
all year round
Choose your section
Three different sections depending on the distance, gradient and how you feel that day.
Entrago — Buyera
The most spectacular section: 18 km of gentle descent through gorges, tunnels and riverside forest. Shuttle takes you back.
Tuñón — Proaza
11 km completely flat. Perfect for families with small children, buggies or just a quieter pace. Bears waiting at the end.
Proaza — Valdemurio
The most secluded section: 10 km of beech and oak forest leading to Valdemurio reservoir. For those who want silence.
Why the Senda del Oso is different
No cars anywhere on the route
The entire route runs on the old railway track. No road crossings, no traffic. Kids can pedal freely from start to finish.
Flat or downhill all the way
The old mining railway never exceeded certain gradients. No technical climbs — even toddlers can complete it with ease.
A living piece of industrial history
Tunnels, old bridges, stone cuttings… The route is a linear museum. Every kilometre has a story from the mining era.
Bears, eagles and otters nearby
The Valle del Oso is one of the highest Cantabrian brown bear density areas in Europe. The Proaza enclosure is free of charge.
Bikes for every style
All rentals include helmet, lock and basic repair kit.
Standard adult bike
The most popular option. Light aluminium frame, 7 gears, perfect for the flat sections.
From 12 €/day
Electric bike
For those who want to enjoy the scenery without getting tired. Recommended for Proaza–Valdemurio.
From 22 €/day
Children's bike (3–12 yrs)
With or without training wheels, according to age and experience. Littlest ones can go in a trailer.
From 8 €/day
Child trailer
For children who can't yet pedal themselves. Attaches to any adult bike. Capacity: 1–2 children.
From 10 €/day
The questions we get most
Do I need to be a cyclist to do the route?
Can I go from Tuñón to Entrago?
How far in advance should I book the bike?
Is there anywhere to eat along the route?
Ready to plan it?
Everything you need before you set off.