Puerto Princesa Underground River: Why Google is celebrating the national park with a doodle

The Puerto Princesa Underground River, one of the world's longest underground waterways, is being celebrated with a special Google Doodle.

The special doodle is to celebrate the seventh anniversary of the Underground River, found in the Philippines, making the Ramsar List of Wetlands of International Importance.

The doodle itself features the entrance to the world-renowned waterway and natural wonder, which stretches for 8.2 kilometres. It also flows into the sea, which makes it the largest subterranean estuary in the world.

Ramsar is an international body created for the conservation of important wetlands and, in 2012, the Puerto Princesa Underground River became just its fifth site.

It also comes a little more than seven years since officially being confirmed as one of the New7Wonders of Nature, which happened on 28 January, 2012. ​New7Wonders of Nature was an initiative started in 2007 to create a list of seven natural wonders across the world, chosen by people through a global poll. Other New7Wonders of Nature include the Amazon Rainforest, Halong Bay in Vietnam and Indonesia's Komodo Island.

It is also a UNESCO World Heritage Site.

Notable species found at the Puerto Princesca Subterranean River National Park, which is a protected area home to the Underground River, include the blue-naped parrot, the bearded pig, the Palawan stink badger, the sea cow, the hawksbill sea turtle, as well as a variety of other lizards, snakes, birds, spiders, bats and more than 800 plant species.

It is also home to the endangered Philippine cockatoo and the endangered green sea turtle.

A spokesperson from Google said:

Aside from celebrating the destination, we hope that this effort serves as a reminder to do our part in conserving it.

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