Crystal Tokyo is the second Silver Millennium situated on the 30th Century Earth. Usagi and Mamoru rule it under the names of Neo-Queen Serenity and King Endymion, and they will have a daughter named Princess Usagi Small Lady Serenity. The Earth becomes one kingdom as it was long ago.
The Guardian Senshi protect the entire royal family, with the Outers acting as outside protection. Luna, Artemis, and Diana live in the palace as well.
At the centre of the kingdom stands the Crystal Palace, where the Royal Family and the Guardian Senshi live. It is depicted over water. The crystals only serve as outer protection with a smaller palace, named Serenity's Palace, located in the top middle spire.
Exposure to the Silver Crystal renders all of Earth's inhabitants functionally immortal. Anyone not born in Crystal Tokyo becomes essentially locked at their current physical age, as shown by the Queen and King Endymion and the Guardian Senshi court, who all appear as if aged in their early twenties. Anyone born in Crystal Tokyo has a slow growth-rate – Small Lady, for example, is stated in the manga to be over 900 years old, yet has the body and mind of a child. According to her parents, such an extremely slow growth is irregular.