By the deep sea, (the) music in its roar,
I love not man the less, but nature more,
From these our interviews, in which I steal
From all that I may be, or have been before,
To mingle with the universe, and feel
What I can ne'er express, yet cannot all conceal
Viking house at the rear of the beach at Sandwick
Shetland has approximately 900 miles of indented coastline consisting partly of exposed cliffs and shores bordering both the Atlantic Ocean and the North Sea. No part of Shetland is more than 5 km from the coast; the sea and the coastline are central to life in Shetland.
Grind of the Navir from the south
In the words of Flinn (1977), "Shetland is a partly drowned range of hills rising rather sharply from a depth of about 82 m below present sea level". The submergence of the archipelago has had a profound effect on coastal processes, allowing deep water waves to approach parts of the outer coastline directly and without breaking and the progressive reworking of depositional features on the middle and inner coasts. The outer coast displays spectacular cliff scenery, reflecting rapid erosion along one of the highest energy coastlines in the world. The middle coast is much more sheltered and includes the anchorages of Sullom Voe and Bressay Sound, where deep water fills drowned glacial valleys. The sands and gravels along the inner coast are highly mobile, with beaches, spits and bars adapting to sea level rise and being reworked during major storms.
In terms of Valentin's classification of coasts, Shetland falls into the "Submergence and erosion" quadrant. Its coastal landscapes are amongst the best in the world in this category.
The recent submergence of Shetland is apparent in the fine detail of its coastline. Peat formerly developed on boggy surfaces above sea level is now often found at or below sea level and sometimes buried beneath boulder and gravel beaches. The coastal edges of Shetland’s few sandy coastlines frequently take the form of a small, sandy cliff, suggesting progressive erosion. Many archaeological sites in bay heads have been exposed by (and in some cases partly destroyed by) coastal erosion. At Sandwick on Unst, the remains of a late Norse longhouse stand in place on the upper part of the present beach. The progressive submergence has given little opportunity for shore platforms to develop, while on the outer coast the cliffs usually plunge into deep water.