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The Planky Town is a trading town that lies at the mouth of the Greenblood in Dorne, near Lemonwood. It has a harbor that sees trading vessels. The orphans of the Greenblood trade with merchants from across the narrow sea at the Planky Town.
During the Conquest of Dorne, Alyn Velaryon broke the Planky Town and sailed up the Greenblood while most of the Dornish strength was in the Prince's Pass. The game of cyvasse was introduced to Westeros by a Volantene trading ship at the Planky Town. It was spread by the orphans traveling the Greenblood and soon the Dornish court learned to play the game.
A Dance with Dragons