la Cort Fosca

La Cort Fosca is one of the most intriguing caves in the municipality of Mura, tucked into the southeast slope of the Serra de la Fosca within the Sant Llorenç del Munt i l'Obac Natural Park. Its entrance, shaped like an inverted V, is almost completely hidden behind vegetation, so spotting it on your own feels like a genuine discovery. The site has long drawn hikers, amateur speleologists, and history enthusiasts exploring the Bages region.

How do you get there?

The cave is best reached on foot, either from Mura itself or from the nearby Hospital de Sang, a former refuge for the wounded during the Carlist Wars that sits right next to Cort Fosca. The route forms part of a popular loop through the Natural Park, linking caves, old shelters, medieval rock-cut tombs, and a supposed prehistoric astronomical observatory. The trail winds through the typical landscape of the Sant Llorenç del Munt massif — rocky ridgelines, dense scrub, and valleys covered in Mediterranean forest. No climbing gear is needed to reach the cave itself, though sturdy hiking boots are strongly recommended.

What will you see?

Cort Fosca stretches roughly 110 meters and splits into two main sections. The first, near the entrance, is a chamber containing a round stone believed to have served as a hearth — a trace of the cave's past use as a shelter. The second, deeper chamber holds the Font Fosca, an underground spring. About 25 meters from the entrance lies the Rossinyol spring, fitted with a masonry water-collection system that once served the surrounding farmsteads.

Inside, visitors find striking rock formations, natural water-filled hollows, and steady drips falling from the ceiling. Because the passage curves and no daylight reaches the interior, a flashlight is essential — without one, exploring the cave simply isn't possible. Documented Iberian-era finds have been recorded here, though the site has never been formally excavated or published, leaving its past still wrapped in some mystery.

The name "de Matarodona" comes from a nearby farmhouse on whose land the cave sits. Right beside it stands the Hospital de Sang, used to treat the wounded during the 19th-century Carlist Wars, adding a layer of history to the visit.

When should you visit?

Spring and autumn are the best seasons, when temperatures across the park stay mild and the vegetation cloaking the cave entrance is at its lushest, making the approach even more rewarding. Summer heat can be intense on the exposed stretches of the Sant Llorenç del Munt massif, so an early start is wise. Winter brings quieter trails, though the cave's interior stays cool and damp year-round regardless of the season outside.

Frequently asked questions

Do I need a flashlight to enter the cave? Yes, it's essential. The passage curves and daylight doesn't reach beyond the entrance, so without your own light source you won't be able to explore the interior.

Is the route suitable for families with children? Reaching the cave doesn't require any climbing skills, but the interior itself — curved, dark, and damp in places — is best explored with older children under adult supervision and with proper lighting.

What else is nearby Cort Fosca? Right next door stands the Hospital de Sang, a former Carlist War refuge, and close by is the Rossinyol spring with its masonry water-collection system. The route also connects to other park landmarks such as Cova Malpàs and Turó de la Pola.

Has the cave been archaeologically studied? Iberian-era finds have been documented there, but the site has never been formally excavated or published, so many questions about its history remain open.