Ventana del Relux desde el Mazo

The “Ventana del Relux” is a work of art from nature, a stone arch located above a gorge that separates Biscay from Cantabria, in Peña del Mazo (Karrantza). It is a simple route that offers spectacular views of the valley and its borders with neighbouring Cantabria.

To start the itinerary, we will leave by car from the Concha district (Karrantza) in the direction of Lanestosa until the ascent to Puerto del Alto Ubal (635 m). Once in Ubal, we follow the signs to the summit of Mazo on a paved road for about 1.8 km. We arrive at a farm where we leave the car (on the banks, without disturbing its operation) and start the journey on foot.

The ascent will offer us a breathtaking view of Karrantza. We will cross a fence and cross a strange meadow until we reach a path that passes between the rocks.

The "Ventana del Relux" cannot be seen until you are in front of it, which makes the surprise even bigger. Through the arch, we can admire the view of the villages in the far east of Cantabria and even, on a clear day, we can view the sea.

* Not recommended on foggy and misty days.