Dragonstone is the name Daenerys Targaryen gives to a hill in the Dothraki sea, naming it after her birthplace, the island of Dragonstone. It is located east of Vaes Diaf.
The hill appears as a stony island within the green grassland of the Dothraki plains. Scrub grass and thorny bushes cover its lower slopes, while a jagged tangle of bare rock thrusts into the sky. There is a shallow cave amidst the broken boulders, razor-sharp ridges, and needle spires. There are fish in a nearby spring-fed pool.
A Dance with Dragons
After having fled Meereen atop Drogon, Daenerys Targaryen ends up in the Dothraki sea. She stays within the dragon's lair, a cave in a hill she names Dragonstone.