Andalos, also known as the Hills of Andalos, is a region of Essos which is the ancestral homeland of the Andals, who migrated to Westeros a long time ago. Andalos was orginally home to a race of Hairy Men who were related to the men of Ibben.
Andalos is located south of Braavos, east of Westeros, and west of Norvos. Andalos is made up of hills, most notably the Velvet Hills, and planes. The southern marches of Andalos are known as the Flatlands. The Rhoyne runs through Andalos.
Andalos was once a powerful and great kingdom extending across much of northwestern Essos, west of the Rhoyne, including the Velvet Hills and the Flatlands. It was a contemporary of the early Rhoynar Kingdom, and according to Rhoynish histories, the Rhoynar taught the Andals how to forge iron (disputing Andal legends, which insists they were directly taught by the Smith).
The first king of this realm was Hugor of the Hill, who stylized himself the King of the Andals.