Hellholt is a castle in Dorne, the region controlled by House Martell of Sunspear, and the seat of House Uller. The castle is located in the south west of Dorne near the Brimstone. It is east of Sandstone.
In the books
In the A Song of Ice and Fire novels Hellholt is the seat of House Uller. It is located in the Dornish desert, and is difficult to reach overland. The castle is named after an unpleasant event in which unwelcome visitors to the castle were locked up and burned to death.
In "A Feast for Crows", Arianne Martell travels to Hellholt with Myrcella, planning to crown her there in order to provoke the Lannisters into war. The plans fails as Arianne's party is intercepted by Areo Hotah.
In the first of Arianne's sample chapters of "The Winds of Winter", it is mentioned that Ellaria is currently travelling to Hellholt with her daughter Loreza.
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