From A Wiki of Ice and Fire
Driftmark is an island near Dragonstone. It is the seat of House Velaryon. It has a long point. During the reign of Viserys I there were at least three towns in Driftmark: Hull, High Tide and Spicetown
During the Dance of the Dragons, Driftmark was used to launch Black ships to block access to Blackwater Bay. The towns on the island, High Tide and Spicetown, were destroyed in the Battle in the Gullet.