Dragonstone

From Asoiaf

Dragonstone is a castle and an isle. Stannis Baratheon is the current Lord of Dragonstone. (GoT, App)

Dragonstone is a rocky island in the narrow sea.

House Targaryen escaped to Dragonstone following the Doom of Valyria. Aegon the Dragon and his sisters Visenya and Rhaenys Targaryen sailed from here to conquer the Seven Kingdoms.

283 AL Rhaella and her son Viserys III Targaryen fled to Dragonstone after the Sack of King's Landing.

284 AL Queen Rhaella Targaryen died giving birth to Daenerys Targaryen her daughter with Aerys II Targaryen, King of the Seven Kingdoms. At the same time a raging storm smashed the Targaryen fleet at anchor.

The garrison of Dragonstone was prepared to sell of the last two Targaryens when Ser Willem Darry and four loyal men broke into the nursery. He took Viserys and Daenerys with him to Braavos. Soon after Stannis Baratheon sailed for Dragonstone.