The Atlantic Equatorial coastal forests form the southernmost part of the Lower Guinean forests complex, a region of coastal moist broadleaf forests that extend north and west into southwestern Cameroon and southern Nigeria. The Atlantic Ocean lies to the east, and pockets of the Central African mangroves can be found along the brackish river mouths and estuaries along the coast. The Sanaga River in Cameroon marks the boundary between the Atlantic Equatorial coastal forests and the Cross-Sanaga-Bioko coastal forests to the north. To the east, the coastal forests transition to the Northwestern Congolian lowland forests, part of the vast Congolian forests complex that covers the Congo Basin. The Western Congolian forest-savanna mosaic bounds the Atlantic Equatorial coastal forests to the southeast.