Where is Driftmark?
An island off the eastern coast of Westeros in Blackwater Bay, Driftmark sits just west of the castle Dragonstone and is the historic home of House Velaryon, an old Valyrian house notable for its naval power.
Driftmark's Significance in "House of the Dragon"
During the Dance of the Dragons, Driftmark serves as a key rallying point for Corlys Velaryon's forces. By the time of "Game of Thrones," House Velaryon's power has severely diminished, as has the importance of Driftmark.