Hellholt

House Uller raised this castle deep in the Dornish desert during the Andal Invasion, on the banks of the Brimstone, beyond the Vaith. The name has nothing to do with geography or old legend — it comes from a dinner. An Uller lord invited his enemies to a feast, barred the doors of the hall, and burned them alive inside. No one ever called the fortress anything else again.

During the First Dornish War, Lord Harlen Tyrell marched his army across the desert toward Hellholt. Heat and thirst killed many of his men before the walls even came into sight, and when they finally arrived, the castle stood empty. Tyrell ordered a retreat toward Vaith. Neither he nor his soldiers were ever seen again — the desert swallowed them whole, without a trail for anyone to follow.

Aegon the Conqueror and Queen Visenya burned Hellholt, Vaith, and Spottswood in 9 AC. A year later, in answer to Dornish raids on the Reach and the Dornish Marches, Queen Rhaenys rode against the castle on Meraxes. Its defenders did what no other army in Westeros had managed: they brought down the dragon and killed the queen. As Meraxes fell, it tore away Hellholt's tallest tower and part of its wall.

Over the two years that followed, Aegon and Visenya burned Dorne again and again, in what is remembered as the Dragon's Wroth. Around Hellholt the sand melted under Balerion's breath and hardened into glass in places across the desert.

Meraxes's bones stayed where the dragon fell, bleaching in the sun for decades. Generation after generation, young Dornish lords made the journey to Hellholt just to see them — proof that a dragon, and a Targaryen queen riding it, could fall before Dorne's walls.

Centuries later, Princess Arianne Martell chose Hellholt as the place to crown Myrcella Baratheon queen of the Seven Kingdoms. The plan never came to pass: her party was intercepted and captured before they reached the castle.