Gently downhill from Entrago to Buyera, with the return transfer included.
The Ruta del Oso began life as a railway line, and that makes it the most rewarding bike ride in Asturias: an average gradient of 1.5%, a compacted gravel surface and not a single crossing with cars.
But the reason nine out of ten visitors do it on a bike is a different one: on two wheels, the whole route fits into a single morning.
The classic plan sets off from Entrago and rolls down the Teverga valley: 18 km of gentle descent (200 metres of drop in your favour) to the Buyera rest area, with the old railway tunnels, the Valdecerezales gorge and Molina's bear enclosure as the stops.
Taken calmly, with photos and a sandwich, it is 2-3 hours, and at the end there is no riding back the way you came: the return van transfer is included with the rental.
200 metres of drop in your favour: any slope you meet, you will be going down it.
Set off between 10 and 11: Molina active in the enclosure, the heat dodged and a table waiting in Proaza or San Martín.
No surprises
The real difficulty is low: if you ride a bike now and then, you can do it; and if you never ride, you can too — the Entrago–Buyera descent forgives everything.
The only two honest exceptions: the full out-and-back (44 km), which does ask for some stamina, and the Quirós branch, the only stretch where you feel the gradient on the climb towards Santa Marina.
What most people choose: serviced mountain bikes with smooth gears, for ages 12 and up. More than enough for the classic downhill plan.
Worth it for the out-and-back, for the Quirós branch and for groups with mixed levels — the assistance evens out the strong rider and the struggling one.
The tandem for couples who want to chat their way down; the tricycle, very stable, for anyone who does not trust their balance.
Every rental includes helmet, insurance, a route map, on-route assistance and the transfer back from Buyera. If a tyre punctures or someone grinds to a halt, it is not your problem: that is what the assistance is for.
The ones people ask for most at the rental point
18 km gently downhill with the long tunnels, Valdecerezales and Molina's enclosure. The plan most people choose, with the return transfer included.
10 km between the Peñas Juntas gorge and the bear enclosure: a concentrated dose of trail for a free morning.
The quiet arm towards the Valdemurio reservoir and its walkway. The only section with a climb: this is where the e-bike earns its keep.
Real 2026 prices
Full-day rates — set off when you like, stop for lunch and hand the bike back without watching the clock: adult €28, e-bike €50, kids' bike €25-28 by size, tag-along €25, child trailer €25, baby seat €15, dog trailer €25, tricycle €35 and tandem €56.
No hidden extras: helmet, insurance and transfer are all in the price. Pick-up in Entrago (Polígono de Pradacón, Nave 1) with free parking; free cancellation up to 24 hours before — and if it rains, on the day itself.
The family outing
The Senda is the easiest family bike ride in Asturias, and that is not just a slogan: a compacted surface "perfect for small wheels", no cars at all, and stops with a payoff — tunnels that feel like caves, bridges over the river and a real bear.
The itinerary that works: Entrago–Buyera downhill, a long stop at Molina's enclosure (best before 11) and a paddle in the river in summer. If your crew is very small, the route on foot has the short pushchair-friendly versions.
From 8-9 months old, with a 5-point harness, adjustable footrests and side protection.
Ages 1 to 5, up to 2 kids and 30 kg. The mid-route nap is guaranteed.
Ages 4 to 8: they pedal when they feel like it, you steer at all times.
Ages 5 to 12, in 16", 20" and 24" sizes, with helmets to match.
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