Lagoa Mundaú is a striking estuarine lagoon situated just west of Maceió, the capital city of Alagoas state in northeastern Brazil. Covering approximately 23–24 square kilometers, the lagoon stretches roughly 14.22 km in length and 4.22 km at its widest point, making it a substantial coastal water body with significant ecological and cultural importance. Fed primarily by the Paraíba do Meio River and the Mundaú River, the lagoon drains eastward into the Atlantic Ocean and is also connected to the neighboring Manguaba Lagoon through an intricate network of canals that weave across a low-lying coastal plain, creating a mosaic of small islands, channels, and mangrove-fringed waterways. The municipalities of Santa Luzia do Norte and Coqueiro Seco, along with portions of Maceió itself, border the lagoon's shores. This estuarine environment supports extensive mangrove forests and a rich assemblage of fish, crabs, shrimp, and shellfish, making it a vital resource for local fishing communities who have worked these waters for generations.