Puerto de la Sia is a classic climb in the Cantabrian Mountains

Puerto de la Sia is a classic climb in the Cantabrian Mountains

Spain, europe

Length

4.8 km

Elevation

1,229 m

Difficulty

hard

Best Season

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

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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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