aquamarine bay blue boulder coast energetic energy fierce inlet island landscape Maddalena Islands natural nature powerful rock rocky Sardinia sea shore strong summer wave bottom destination distance distant holiday horizon leisure peace placid relax ripple view water clear coastline cool granite inviting islands Maddalena mediterranean refreshing shoreline vacation anchorage anchored boat dinghy mast moored pleasure rest sail sailing sport tourism yacht abundant covered dried eerie marine maritime matted Neptune-weed odd plant Posidonia Remains sea-grass strange unusual vegetation boulders gray grey land pink rough rugged sky isthmus spit carved coastal eroded erosion form formation macabre ship trawler weird tide