Arrafela

Arrafela is a sima — a natural vertical cave shaft — located in the Urbasa-Andía Natural Park in Navarre, within the Urbasa mendia mountain range. Once known mainly to local cavers, the site drew wide attention in 2026 after a striking paleontological discovery revealed thousands of years of natural history hidden inside it.

What is Arrafela?

Arrafela is a vertical karst cave, also known locally as Sima de los Fusiles (the Rifles' Pit) or Sima Arrafela-I. It sits within the extensive karst system of the Urbasa-Andía massif, alongside other nearby shafts such as Tximua and Bixenteliyesota. Reaching the bottom requires caving experience and rope-descent equipment — this is not a tourist cave in the conventional sense, but a natural fissure cutting through the rock of a mountain plateau.

What will you see? The discovery that changed everything

In February 2026, a multidisciplinary team of scientists found an almost complete bison skeleton inside Arrafela, roughly 4,000 years old, with an arrowhead still embedded in its bones. That find turned out to be part of a much larger deposit: researchers also recovered the remains of a cave lion (Panthera spelaea), a predator extinct for around 12,000 years — one of only a handful of documented specimens in Navarre, and the most complete one found so far. Bones from a capercaillie and various birds of prey were also unearthed inside the shaft. Given the range and richness of the fossils, scientists have described Arrafela as a kind of time capsule, preserving a record of the region's ecosystem across thousands of years.

Because excavation work is ongoing and the finds are fragile, the inside of the cave is not open for casual visits — it currently functions as an active archaeological and paleontological site. The main draw for visitors, then, is the surrounding landscape of the Urbasa-Andía massif itself: a karst plateau covered in beech forest and pastureland, dotted with dozens of similar natural shafts.

How do you get there?

Hiking and caving routes crisscross the Urbasa-Andía Natural Park and lead through the area around Arrafela, including trails that link several nearby simas — Tximua, Arrafela (Los Fusiles), and Bixenteliyesota — popular among hikers and cavers exploring the region. The park itself stretches across Navarre and ranks among northern Spain's most significant karst areas. Given the terrain — uneven, rocky, and dotted with sinkholes — it's worth sticking to marked paths and wearing sturdy footwear.

When should you visit?

Spring through early autumn is the best window for exploring the Urbasa-Andía area, when mountain weather is more stable and trails stay dry and safe underfoot. In winter, the plateau is often shrouded in fog and exposed to strong winds, making it harder to navigate safely around the many natural shafts scattered across the terrain.

Frequently Asked Questions

Can you descend into the Arrafela cave? Descending requires caving skills and equipment, and access is further restricted right now due to the active scientific excavation — it isn't an attraction open to casual visitors.

What was discovered in Arrafela in 2026? An almost complete bison skeleton around 4,000 years old, with an arrowhead embedded in its bones, along with remains of a cave lion (Panthera spelaea) from roughly 12,000 years ago, plus bones from a capercaillie and birds of prey.

Where exactly is Arrafela located? Within the Urbasa-Andía karst massif in Navarre, Spain, near other shafts such as Tximua and Bixenteliyesota.

Is the area worth visiting even without entering the cave? Yes — the Urbasa-Andía Natural Park itself is a rewarding destination for hiking, with its beech forests and karst plateau scenery, regardless of access to the cave's interior.