Puerto de la Sia is a classic climb in the Cantabrian Mountains
Spain, europe
4.8 km
1,229 m
hard
Year-round
# Puerto de la Sia
Ready for a thrilling mountain drive in northern Spain? Puerto de la Sia is a stunning pass perched at 1,229 meters (4,032 feet) that straddles the border between Cantabria and Castile and León, nestled in the heart of the Cantabrian Mountains.
The 21-kilometer route runs north-south from the charming village of Espinosa de los Monteros toward the CA-265 road, and most of it is paved—though fair warning, it gets pretty narrow in spots. Expect some serious elevation gain with gradients hitting 10% on certain stretches, so this isn't exactly a leisurely cruise.
At the summit, there's a small parking area and an old, abandoned mountain refuge where you can catch your breath and soak in the mountain views. Want an extra adventure? A rough, unpaved track branches east toward Picón Blanco (1,512m), but this 4.8-kilometer stretch is strictly 4x4 territory and impassable in winter.
The pass stays open year-round for regular traffic, though winter weather can occasionally force temporary closures. The road is known as CA-665 on the Cantabria side and BU-571 on the Castile and León side—useful to know if you're plugging it into your GPS.
This is one for drivers who don't mind a challenge and love high-altitude scenery.
Where is it?
Puerto de la Sia is a classic climb in the Cantabrian Mountains is located in Spain (europe). Coordinates: 40.1230, -2.4153
Road Details
- Country
- Spain
- Continent
- europe
- Length
- 4.8 km
- Max Elevation
- 1,229 m
- Difficulty
- hard
- Coordinates
- 40.1230, -2.4153
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