adapted from Wikipedia
Pénglái Island is a mystical island in the eastern end of Bóhǎi Sea, along with four other islands where the Immortals live, called Fāngzhàng (方丈), Yíngzhōu (瀛州), Dàiyú (岱輿), and Yuánjiāo (員嬌).
This group of islands is the base for the Eight Immortals, or at least where they travel to have a banquet, as well as the Daoist sorcerer Ān Qīshēng, who knows how to brew the elixir of life. Supposedly, everything on the mountain seems white, while its palaces are made from gold and platinum, and jewellery grows on trees.
There is no pain and no winter; there are rice bowls and wine glasses that never become empty no matter how much people eat or drink from them; and there are magical peaches growing on Pénglái Island that can heal any disease, grant eternal youth, and even raise the dead.
As noted before, The Immortals of Kūnlún and the Immortals of Pénglái are separated by a bitter rivalry.