Angus has some of the most dramatic and varied coast line in Scotland ranging from dramatic sandstone cliffs and sea stacks to extensive beaches and sand dune networks. To the north and west, the area is mountainous, known locally as the Angus Glens which now form part of the Cairngorms National Park. Angus has been occupied since at least the Neolithic period. Bronze age archaeology is to be found in abundance in the area. There are visible remnants of the Pictish age with numerous sculptured stones. Angus is marketed as the birthplace of Scotland. The signing of the Declaration of Arbroath at Arbroath Abbey in 1320 marked Scotland's establishment as an independent nation.