Bear Trail Activity · Proaza, Oviedo, Asturias The Senda del Oso, a nature trail and greenway, runs through the concejos of Proaza, Teverga, Quirós and Santo Adriano along the old bed of the mining railway that, until its closure in 1963, brought iron ore and coal down the valley of the river Trubia from Santa Marina and the mines of Teverga to the village of Trubia. The Principality of Asturias approved its restoration in 1991: the first stretch, between Tuñón and Proaza, opened in 1995, and the second, 18.5 kilometres long between Caranga and Cueva Huerta, in 1996, crossing the sierra de Caranga and the Peñas Juntas gorge. Altogether it totals about thirty-six kilometres of tunnels and gorges along the river Trubia. In Proaza is the enclosure where the she-bears Paca and Tola once lived. Photo: Sammy pompon (CC BY-SA 4.0) What to see and do in Proaza