Port Cave (Cueva del Puerto) in Calasparra

Port Cave (Spanish: Cueva del Puerto) is a cave in the municipality of Calasparra, in the Murcia region of southeastern Spain. It holds the record for the largest horizontal cave system in the region, with close to 5 km of surveyed passages out of roughly six kilometers of known galleries in total. The cave is hypogenic in origin, meaning its passages were not carved by surface rainwater but by hot thermal waters rich in sulfuric acid and CO2, which dissolved the surrounding limestone over millions of years. This process began around 15 million years ago and produced a network of chambers with unusual rock formations rarely found elsewhere.

How do you get to Port Cave?

The cave sits about 14 km from the center of Calasparra. It is reached via the RM-714 road, which connects Calasparra to the village of Venta del Olivo — the route is signposted and does not require driving off-road. A car is the practical option, since public transport in the area is limited, and parking is available right at the cave entrance.

What will you see inside?

The tourist route winds through a series of distinctive chambers, each named after its appearance — among them the Jellyfish Room (Sala de la Medusa), the Gaudí Room, the Sistine Room, and the Roots Room (Sala de las Raíces). Each one displays mineral formations shaped by thermal water activity, differing noticeably from the classic dripstone formations found in ordinary karst caves. The standard visit lasts 60–70 minutes and is designed to be accessible to visitors of any age, with no prior caving experience needed.

For those after something more demanding, the cave also offers sport routes that descend deeper into the system, reaching the Gran Diaclasa, a large rock fissure that ranks among the site's most striking geological features. Because of its hypogenic characteristics, Port Cave is regarded by researchers as a reference model for this type of cave in Spain, and it has hosted speleological conferences focused on hypogenic caves across the Murcia and Valencia regions.

When is the best time to visit?

The cave is open for visits year-round, and the internal temperature stays stable regardless of the season — a welcome relief from Murcia's summer heat, and equally comfortable in winter. Because the number of spots on each tour is limited, it's worth booking ahead, especially on weekends and during peak holiday periods when demand is highest.

Do you need to book in advance?

Yes — entry is only possible with a prior phone reservation. Walk-in visits are not accommodated, so you need to call ahead and arrange a time slot before arriving.

Frequently asked questions

How far is Port Cave from central Calasparra? About 14 km, reached by the RM-714 road heading toward Venta del Olivo.

How long does a visit take? The standard tourist route runs 60–70 minutes and suits visitors of any age or experience level.

Is the cave suitable for children and older visitors? Yes, the standard route is designed to be accessible for families with children as well as older visitors.

What makes Port Cave different from a typical karst cave? It's a hypogenic cave — its passages were shaped by hot, sulfuric-acid- and CO2-rich thermal water rather than surface rainwater, producing unusual rock formations rarely seen in other caves in the region.