The dunes are the main reason many travellers push on to Atins. Tours from the village reach lagoons such as Lagoa das Sete Mulheres and Lagoa Tropical, with fewer vehicles than the classic Barreirinhas circuits when conditions line up.
The lagoons change with the rain. They usually look best after the wet season, when freshwater pools still sit between the white dunes. Ask locally which route is worth it that week, because names matter less than water levels.