Murcigallinos Cave

Murcigallinos Cave is a small cave in the province of Segovia, close to the village of Basardilla at the foot of the Sierra de Guadarrama. Administratively it sits within the neighboring municipality of Losana de Pirón, in the hills above the Pirón river, but Basardilla is the nearest well-known settlement and the natural base for anyone wanting to explore this corner of Segovia.

Where is the cave located?

Murcigallinos Cave lies in an area known as El Soto, on private land, above the better-known Cueva de la Vaquera and right at the edge of a rock cliff. The landscape here is typical of the Guadarrama foothills: limestone ridges cut by river valleys, where caves and rock shelters have formed over millennia. Because the land is privately owned, the cave itself is not freely accessible to visitors — it is best treated as a landmark to view from outside rather than a site to explore inside.

What can you see around the cave?

The cave formed in a similar way to the nearby Cueva de la Vaquera, one of the region's most important archaeological caves, but sits higher up, right at the cliff edge. Inside, visible sediment layers appear both at the entrance and along the back wall, and some of these layers contain embedded fossils. That gives the site geological as well as natural interest, even when viewed only from the outside.

Because of the presence of several bat species, Murcigallinos Cave has been designated a Lugar de Interés Comunitario (Site of Community Importance) under the EU's Natura 2000 network. The cave's own name is a nod to bats — in the local Segovian dialect, bats were traditionally called "murcigallinos." For wildlife enthusiasts and anyone interested in protected species, it is one of the more distinctive sites in the area.

What archaeological finds have been made here?

Excavations inside the cave uncovered fragments of Bronze Age pottery along with animal bone remains, most of them badly fragmented and difficult to identify precisely. These finds confirm that the area was used by humans since prehistoric times, much like many other caves scattered along the Pirón valley that have served as shelters for thousands of years.

When to visit and what else to see in Basardilla?

Basardilla is a small village sitting at around 1,010 meters above sea level, between Torrecaballeros and Brieva, with part of its municipal area falling inside the Sierra de Guadarrama National Park. Its name has Roman roots and translates roughly as "valley of brambles." In the village itself, the Romanesque church of San Bartolomé, built in the mid-12th century, is worth a stop — it has two apses and a richly decorated three-arched portal, and was declared a Cultural Heritage Asset of Castilla y León in 1994. Nearby, the Ermita de la Virgen del Pedernal offers views toward other hilltop shrines in the region.

Spring and autumn are the best times to visit, when temperatures in this foothill part of Segovia are mild and the trails around Basardilla and the Pirón valley are most pleasant for walking. Summers can get hot, while winters bring cold, windy weather typical of this altitude.

Frequently Asked Questions

Can you go inside the cave? No — Murcigallinos Cave sits on private land, so visits are limited to viewing it from outside rather than entering.

Why is the cave protected? It hosts several bat species and has been listed as a Site of Community Importance under the EU's Natura 2000 network.

What has been found inside the cave? Archaeologists have found Bronze Age pottery fragments and fragmented animal bones, evidence that people used the site in prehistoric times.

What else is worth seeing in Basardilla? The 12th-century Romanesque church of San Bartolomé, the Ermita de la Virgen del Pedernal, and hiking trails running through the Sierra de Guadarrama National Park.