Tam Giang Lagoon lies immediately behind Thuan An Beach, separated from the South China Sea by a narrow strip of sand. The lagoon stretches north and south in both directions, and its shallow, brackish waters support a vast fishing economy. Boats of all sizes work the lagoon at all hours, and at dawn the light on the water is extraordinary.
Boat trips into the lagoon can be arranged from Thuan An Beach. The floating villages — clusters of houses on rafts connected by narrow gangways — are a remarkable sight. Residents raise fish in nets beneath their homes and seldom go ashore more than necessary. The lagoon is also an important staging ground for migratory birds, and the birdlife is most varied in November and December.