House Gargalen of Saltshore is a vassal house which holds fealty to House Martell of Dorne. Their seat is at Saltshore, the southernmost castle in Dorne, and thus also the southernmost castle in Westeros.
House Gargalen's heraldry consists of a red cockatrice on a gold field.
Joffrey mentions Saltshore to Sansa, saying how lords will travel to their wedding from Last Hearth in the north to Saltshore in the south.
In the books
In the A Song of Ice and Fire novels, House Gargalen are the lords of Saltshore.
Houses from Dorne