Asturias road to Casielles features 23 curves and 21% gradients

The road leading to Casielles in the Ponga council of Asturias features a challenging ascent characterized by 23 curves and a nearly 500-meter elevation gain over just 3.5 kilometers. The steep terrain includes ramps reaching gradients of 21%, presenting a significant physical challenge for cyclists.

Constructed on a narrow mountainside, the road's layout is heavily dictated by the complex local topography. While the route has provided essential connectivity to the small settlement since its completion in 1979, its winding and narrow nature remains a defining feature of the landscape.