Technology has enabled man to map and scan almost every corner of the planet. You can get a satellite map of any mountain summit before you even set foot on its slopes. Sonar can give us an idea of the canyons and basins that make up our ocean bottom. But to know what a particular cave looks like, you have to go in and see it for yourself. You have to physically survey and map the cave, plumb its depths and set your eyes on its wonders.

Caves are testament to both the power and patience of water. Naturally, acidic rain reacts with limestone, the most ideal type of rock for cave information, by dissolving it bit by bit. The water seeks weakness in the rock, cracks and seams that will allow it to drip and flow. Over time, this relentless attack by rain together with the unpredictable changes in the limestone structure creates vast networks of corridors, tunnels and rooms both tiny immense, with neither patter nor order. Passages cross over each other without ever meeting, and small openings can lead to huge galleries big enough to swallow a stadium. The dissolved limestone flows into the cave, dripping and flowing to form incredibly beautiful and intricate sculptures, some as delicate as spider webs and other robust and huge as Greek columns. Over the centuries, what started as a slight trickle will eventually become a sparkling curtain of translucent crystals? The Philippines has all the ingredients for making great caves: it has large deposits of limestone and even larger amounts of rains.