KEY POINTS:
The Grand Canyon, Mount Fuji and the Amazon rainforest are likely contenders in a global poll of millions of people to select the seven natural wonders of the world, organisers say.
Around 300 suggestions from six continents have come in so far. Starting in January 2009, people will be able to vote for their favourite sites by internet, mobile phone or telephone, according to the nonprofit foundation New7Wonders.
The organisers have turned to highlighting the most impressive natural wonders after their success earlier this year in the selection of the seven structural wonders, including India's Taj Mahal, the Great Wall of China and Rome's Colosseum.
Over 100 million people participated in the first contest, which concluded in July. Also chosen as manmade wonders were Peru's Machu Picchu, Brazil's Statue of Christ Redeemer, the rock city of Petra in Jordan and Mexico's Chichen Itza pyramid.
Swiss-Canadian adventurer Bernard Weber, who started the foundation in 1999, said his aim is to "create respect and enthusiasm ... for the beauty of our planet".
The new wonders should be places with striking natural beauty, Weber said.
"The closer we bring the beauty of our planet ... to the people, the more likely they will say, 'Oh, we have to do something to conserve it'," he said.
It will take several years to complete the selection. The multi-step process was launched in July, with the public invited to make suggestions for sites to be considered. Suggestions are already posted by continent on the website.
Internet users who nominate a site to be among the finalists must fill in a form with contact details for the authority responsible for the site. Organisers will then contact the authority to ask that an official committee be created to support the contest process.
Once the committee is created, the public can vote - by internet only - to include the site among contest finalists. That voting will continue through the end of 2008.
In early 2009, the 77 sites that have received the most votes will go before a panel of experts, which will choose the 21 finalists.
People will then be able to vote via the web, text message or phone on the final seven.
The winners will be announced in late 2010.
The campaign is meant to be a popular campaign rather than a scientific exercise, Weber said.
The Zurich, Switzerland-based foundation is run by about 20 people and is funded through income from broadcasting rights.
Among the suggestions already received are places like Mount Everest, Ireland's Cliffs of Moher, Russia's Lake Baikal, Ecuador's Galapagos Islands, Egypt's Mount Sinai, Vietnam's Ha Long Bay, Tanzania's Serengeti National Park and Australia's Ayers Rock.
* To suggest nominees and learn more go to www.new7wonders.com/natural.php.