The Inner Sea is one of the most heavily traveled and populated bodies of water in Golarion. Formed after Earthfall in -5293 AR reshaped the face of the planet, the Inner Sea divides Avistan and Garund. Before Earthfall, the two continents had been joined by a land bridge. The impact collapsed the connection and allowed water from the Arcadian Ocean to flow in.
The sea is now separated from the Arcadian Ocean by the Hespereth Strait and Arch of Aroden, which is under Chelaxian control. To the east it connects to the Obari Ocean between the nations of Osirion and Qadira.
The Inner Sea is a cradle of humanity, and six powerful nations—Absalom, Andoran, Cheliax, Osirion, Qadira, and Taldor—line its shores, leading to frequent naval battles between these emerging world powers.