From the White Wolf Wiki, the most complete White Wolf reference

The Blessed Isle is the continent-sized (approximately 2000 by 3000 miles) island located at the center of Creation. Surrounded by the Inland Sea and weeks distant from the closest Threshold port, the Blessed Isle is the center of the Realm and the unquestioned dominion of the Dragon-Blooded. It is also home to a variety of significant locations, including the Elemental Pole of Earth, the Imperial Mountain and the Imperial Manse.

Before the Primordial War, the Blessed Isle was the home of the Gods, who abandoned it for the Celestial city of Yu-Shan.