The Yukiryu Island is a winter island located somewhere in the Grand Line.
This is one of the several islands in which Shanks and his crew, the Red Hair Pirates, hang out. He would later receive Rockstar's message about Whitebeard's answer here and decide to go meet him in person.
One Piece Manga and Anime — Vol.
25 Chapter 234 and Episode 151,
Shanks and Red Hair Pirates hang out on the island.
One Piece Yellow: Grand Elements (p. 173),
the island's name is mentioned.