Crystal Tokyo (クリスタル・トーキョー) is the new name of Tokyo in the 30th Century. It has become not only the capital of Japan, but also of the entire Earth. It is a utopia, the epicentre of the new Silver Millennium, at the center of which stands the Crystal Palace.
In the anime, the borders of the city form the shape of a star when seen from overhead. There are various points within the star shape known as crystal points at which members of the Black Moon Clan try to take contol of in the past on Earth.