Carmarthen Bay is an inlet of the South Wales coast, including notable beaches such as Pendine Sands and Cefn Sidan sands. Carmarthen Bay is partially within the Pembrokeshire Coast National Park. The Joint Nature Conservation Committee list Carmarthen Bay and Estuaries as a Special Area of Conservation.

Pendine Sands is a 7-mile (11 km) beach on the shores of Carmarthen Bay on the south coast of Wales. It stretches west to east from Gilman Point to Laugharne Sands. The village of Pendine is close to the western end of the beach.