survived erosion, as have the chalks of England. By the Tertiary period, the tectonic plates were again moving, separating into modern-day North America and Europe with the creation of the Atlantic Ocean. The split occurred to the west of Scotland, leaving a chain of former volcanic sites through the Hebrides, including Skye and St. Kilda. This was the last period of rock formation in Scotland. Physical geography Main points The main points of the Scottish mainland are: North: Easter Head, Dunnet Head, Caithness East: Keith Inch, Peterhead, Aberdeenshire South: Mull of Galloway, Dumfries and Galloway West: Corrachadh Mòr, Ardnamurchan (headland), Lochaber It is often yet incorrectly stated that John o' Groats is the most northerly point of mainland Scotland. The pre-Union phrase "John o' Groats to Maidenkirk" was the Scottish equivalent of the British Land's End to John o' Groats. The extreme points of Scotland, including outlying islands, are: North: Out Stack, north of Unst, Shetland Islands East: Bound Skerry, Out Skerries, Shetland Islands South: Mull of Galloway, Dumfries and Galloway West: Either Rockall (annexed in 1972 to the former Inverness-shire), the international status of which is disputed, or Soay, St. Kilda, Western Isles The geographical centre of Scotland lies a few miles from the village of Newtonmore in Badenoch, far to the north of the modern population heartlands. The geographical centre of the mainland alone lies near the peak of Schiehallion. Land use The total land area of Scotland is 8,023,947 hectares. Grasses and rough grazing account for 67% of the land area, forest and woodland 17%, urban development 8%, crops and fallow 7%, and other agricultural land accounts for 2%. Topography, mountains and hills Scotland contains the most mountainous terrain in Great Britain. Much of the highest uplands lie to the north and west of the Highland Boundary Fault in the Northwest Highlands and Grampian ranges. The jagged Cuillin, on the Isle of Skye, represents a major mountain range that is not located on the Scottish mainland. Located at the western end of the Grampian Mountains, at an elevation of , Ben Nevis is the highest mountain in Scotland and Great Britain. Ben Macdui and Braeriach are, respectively, the second and third tallest peaks in Scotland. Both are located in the Cairngorms, a mountain range in the eastern Highlands which is the highest upland area in Britain. In the south of Scotland lie the Southern Uplands, a vast,