A worldwide campaign for the underground river in Palawan, southwestern Philippines has intensified, following its official entry in an international online contest that is in search for the seven wonders of the world. Filipinos in the Philippines and in other parts of the world were called to use multi-media channels in voting the Puerto Princesa Underground River (PPUR) in the online contest of the New 7 Wonders of Nature. Interior and Local Government Secretary Jesse M. Robredo asked local government leaders to campaign nationwide and encourage residents to go online through several venues such as government offices, the internet cafes and schools, so that they can vote online. Embassies, consular offices, and labour offices of the Philippine government abroad should encourage overseas Filipinos to vote for Puerto Princesa\'s underground river, said a foreign affairs official who requested for anonymity. \"Three was no official order yet, but the campaign for the underground river is being planned overseas,\" said the official. All venues must be open to all Filipinos, said Robredo, adding that Filipinos in the provinces must be encouraged to go online to vote for the underground river. \"This is to ensure the victory of Palawan\'s underground river in the contest of the New 7 Wonders of Nature,\" said Robredo. Since majority of Filipinos have mobile phones, government offices have started campaigning on how to key-in votes for the underground river. Filipinos can use text messages by typing Text PPUR and sending it to 2861. They can also log on to www.new7wonders.com, to vote, said Robredo, now considered a master campaigner for Palwan\'s underground river. Media entities and tour agencies have also joined the campaign. Earlier, President Benigno Aquino expressed optimism that Palawan\'s underground river will get plenty of votes from eight million Filipino mobile phone users. \"This will truly benefit the tourism industry in the Philippines,\" Robredo said. The last day of voting will be on November 10. The awesome underground river is divided in the centre by a limestone outcrop known as the St. Paul mountain range. It rises 1,028 meters at the highest, 11 km long, between 3-5 km wide and covers an area of around 35 sq. /km. Scientists believe it is between 16 - 20 million years old. It was formerly known as the St. Paul Subterranean National Park when it was established as a protected park in 1971. In 1999, the national park was expanded to 22,202 hectares and was renamed Puerto Princesa Subterranean River National Park. On December 11, 2003, the National committee on Geological Sciences declared it as a National Geological Monument. It was first mentioned by Dean Worcester when he was an Assistant Professor of Zoology at the University of Michigan in 1887. Later, he became the Secretary of Interior during the American rule, which began in 1898. From / Gulf News