In 2011, the area received a huge boost, when New7 announced its list of the 7 Wonders of Nature – counting 500 million votes in the process. Puerto Princesa’s stunning underground river - complete with a cavernous, sunken lagoon - beat off wonderful sites like the Great Barrier Reef, to claim a spot on the final, prestigious list. Set sail across the glowing green water, on a journey into the gaping mouth of the limestone caves at Puerto Princesa. Known for being one of the least densely populated, cleanest and most environmentally friendly cities in the Philippines, there’s a raft of natural wonders to explore - from diving hotspots to towering limestone cliffs, and the entrancing underworld of the underground river.