Wikitravel:World Heritage Expedition
The milestone will be considered achieved when articles for all 878 sites on the official UNESCO list have been created and linked in from the UNESCO World Heritage Site page. However, the project will continue indefinitely, as new sites are added yearly (usually in June or July) and the articles of existing sites can always be improved.
How you can help
Remaining countries on current list
As of March 2009 - please remove the relevant countries from the list once stubs for all sights in the country has been created.