WATERMARKS. Water is the most powerful force on earth. It has shaped our landscape more than any other element, carving out mountains and valleys and sculpting our continents. Its energy and power can be seen in our coastline: rugged cliffs pounded by the waves into jagged shards, boulders worn smooth by melting glaciers millions of years ago, stone ground down over millennia to sand now as fine and white as icing sugar. 'Watermarks' explores the faces of the sea and its imprint on our planet.