Lewis - Geography and Geology

Geography and Geology

A cross-section of Lewis would see mostly sandy beaches backed by dunes and machair on the east coast, giving way to an expansive peat covered plateau in the centre of the island. The Atlantic coastline is markedly more rugged and is mostly rocky cliffs broken by small coves and beaches. The more fertile nature of the eastern side led to the majority of the population settling there, including the largest (and only) town, Stornoway. Aside from the village of Achmore in the centre of the island, all settlements are on the coast.

Compared with Harris, Lewis is relatively flat, except in the south-west, where Mealisval, 574m (1,883 ft), is the highest point, and in the south-east, where Beinn Mhor reaches 572m (1,877 ft); but there are 16 high points exceeding 300 m (1000 ft) in height. Southern Lewis also has a large number of freshwater lochs compared to the north of the island.

South Lewis, Harris and North Uist collectively is a National Scenic Area, and there are 4 geographical Sites of Special Scientific Interest (SSSI) on Lewis - Glen Valtos, Cnoc a' Chapuill, Port of Ness and Tolsta Head.

The coastline is severely indented into a number of large sea lochs, such as Lochs Resort and Seaforth which form part of the border with Harris, Loch Roag surrounding the island of Great Bernera and Loch Erisort. The principal capes are the Butt of Lewis, in the extreme north, with hundred foot (30 m) cliffs (the high point is 142 ft (43 m) high) and crowned with a lighthouse, the light of which is visible for 19 miles; Tolsta Head, Tiumpan Head and Cabag Head, on the east; Renish Point, in the extreme south; and, on the west, Toe Head and Gallon Head. The largest island associated with Lewis is Bernera or Great Bernera in the district of Uig and is linked to the mainland of Lewis by a bridge opened in 1953.