Andustar was the western region of Númenor, separated from the Hyarnustar to the south by the wide Bay of Eldanna. It was known as the region which was built the city of Andúnië, the haven of the Faithful. Andustar was roughly rectangular in shape and size, and about 240 kilometres west to east, and 160 kilometres north to south. To the east, it bordered the Forostar and Mittalmar regions, but as a coastal land it was surrounded in all other directions by the Great Sea. It also bordered in the coastal south by the small region of Nísimaldar.