A coastal dune is a hill of sand formed by the wind along the shoreline. These natural structures are typically found in areas where sand is abundant, such as beaches and coastal regions. Coastal dunes play a crucial role in protecting inland areas from storm surges and high waves, acting as a buffer against erosion. Coastal dunes are often covered with vegetation, which helps stabilize the sand and prevent it from being blown away. Plants like sea oats and beach grass are commonly found in these areas, as their roots bind the sand together. This ecosystem supports various wildlife, making coastal dunes important for biodiversity.