Swansea Bay is a bay on the southern coast of Wales. The River Neath, River Tawe, River Afan, River Kenfig and Clyne River flow into the bay. Swansea Bay and the upper reaches of the Bristol Channel experience a large tidal range. The shipping ports in Swansea Bay are Swansea Docks, Port Talbot Docks and Briton Ferry wharves.

River Neath is a river in south Wales running south west from the point at which its headwaters arising in the Brecon Beacons National Park converge to its mouth at Baglan Bay below Briton Ferry on the east side of Swansea Bay.