Lençóis Maranhenses National Park is a protected area on Brazil’s north Atlantic coast. It’s known for its vast desert landscape of tall, white sand dunes and seasonal rainwater lagoons. Lagoa Azul and Lagoa Bonita are two of the largest lagoons. The park’s diverse ecosystem also includes mangrove swamps. The nearby towns of Barreirinhas and Santo Amaro do Maranhão are gateways to the park