Supercave system

 Nearly 16.5 miles long 'supercave system'      

Explorers in southern Spain have linked two deep caves into one “supercave system” about 16.4 miles long. The connection sits inside Sierra de las Nieves near Málaga and pulls together years of careful mapping by volunteer cavers and collaborating scientists. Teams spent decades mapping passages, measuring angles and plotting profiles. They worked methodically from both sides until survey lines converged in a narrow zone. This is classic karst, terrain formed by dissolving rock such as limestone. Acidic water finds fractures, enlarges them and eventually builds caves. The work was led at the Underground Exploration Group of the Excursionist Society of Málaga. Its team focuses on systematic cave mapping and safe access to complex systems.

Early surveys suggest the connected network could eventually extend to roughly 31 miles if nearby passages link up. The new supercave complex also incorporates a known water cave, which hints at a larger underground drainage story. This makes the system a valuable natural laboratory for water tracking in limestone mountains. For Andalusia, the find marks a step change in underground science and hazard planning. Long cave networks can reveal how floods move through rock during heavy rain. This is patient speleology, the scientific exploration of caves. It blends rope work, precise instruments and record keeping to turn darkness into a reliable map. Recent pushes focused on overlooked side routes and tight chimneys which earlier parties bypassed. This careful rechecking paid off when two galleries finally met.

Caves shelter specialized animals which live in constant night. Biologists call them troglobionts, organisms adapted to caves with reduced eyes and pigment. The broader landscape holds UNESCO Biosphere Reserve status, which covers fragile karst habitats and their wildlife. These communities depend on steady temperatures and scarce nutrients. Disturbance can ripple through food webs built on bat guano, microbes and drips. Protecting supercave means limiting traffic, light and noise. It also means keeping mud and lint off formations which took millennia to build. Permits help control group sizes, routes and timing. They also track cumulative impacts on sensitive chambers and seasonal bat roosts. Good practice never goes out of style. Teams pack out every scrap, minimize footprints and leave scientific markers for follow up work.

The project shows why you revisit old data with fresh eyes. Small positional errors can hide a junction for years until improved surveys tighten the picture. Supercave mapping adds missing pieces between recharge zones and outflow points. Better maps support models which predict where water, silt and pollutants will travel. Sierra de las Nieves is a high relief limestone massif where water sculpts voids over time, a setting documented by a geomorphology analysis. Fractures in the bedrock helped in guiding underground development. Water seeks the easiest path along cracks which eventually widen into rooms and shafts. As galleries grow, they connect into a branching network. This network moves storm pulses from uplands to springs, shaping the region’s water budget. Park managers were notified after the breakthrough, and cave visits in protected areas require prior authorization. This point is reinforced in the regional bulletin.

Safety is part of stewardship. Clear callout plans and redundant gear keep rescuers out of harm’s way and reduce pressure on public services. The connection opens years of work for geology, hydrology and biology. Researchers will test airflow, water chemistry and rock stability as the system is mapped. Future campaigns will target junctions where small side tubes might bridge to neighbouring caves. Each new survey leg will be checked against earlier line plots. The team will also refine vertical profiles. Accurate elevation data clarifies how storm water drops through shafts before joining the main drainage. The new complex turns hidden space into a map which anyone can read. It is a reminder that science thrives on patience, precision and shared notes. In time, the system records climate history in minerals which grow from drips. The records help scientists place recent rainfall swings in a longer frame. Supercaves teach teamwork and data discipline. They also show how surface choices, from paving to pumping, can echo underground for a long time in future also.