vast and serene view of authie bay at low tide, with expansive sandy shoreline, calm ocean waters, and a dramatic sky filled with

authie bay beach berck coastal shoreline sand sea ocean tidal low tide wetland nature landscape fortmahon somme hautsdefrance marquenterre picardy northern caacute te daopale france europe mud slikke schorre salt marsh english channel horizon vast calm blue sky clouds dramatic marine wilderness remote isolated seascape panoramic travel tourism environment natural beauty coastline pasdecalais reflection perspective