Shetland Islands, Or Zetland, a group in the Atlantic ocean, forming the northernmost part of Great Britain, mainly extending from lat. 59° 50' to 60° 50' N., and from Ion. 0° 45' to 1° 45' W.; area, about 450 sq. m.; pop. in 1871, 31,608. There are about 100 islands, not more than one fourth of which are inhabited. The largest island is Mainland, which contains about three fifths of the total area and two thirds of the population; and those next in importance are Foula or Foul (the westernmost), Papa-Stour, Muckle Roe, Whalsey, Yell, Bressa, Fetlar, Unst, E. and W. Burra, Fair (the southernmost), and the three Skerries.

Lerwick, on the E. coast of Mainland, is the capital. The coasts are generally bold and precipitous; they vary in height from 500 to 1,200 ft. above the sea, and are indented with numerous deep landlocked bays and by long narrow arms of the sea called voes. The interior is not generally much elevated above the coasts, the highest summit in the group, in the N. part of Mainland, rising 1,476 ft. above the sea. The surface is mostly rugged, or covered with moss, and the only tolerably fertile soil is in a few of the valleys and in the neighborhood of some of the bays. The geological formation consists of sandstone, gneiss, blue limestone, clay and mica slate, and granite. Copper has been discovered on one of the islands, and chromate of iron is exported from Unst. The climate is not remarkably cold, but there is much wet and tempestuous weather, and fogs are frequent. In winter it is dark and dreary, but about midsummer the sun scarcely disappears below the horizon. Very little of the soil is arable. The principal crops are oats, barley, potatoes, and turnips. The live stock on the group are very diminutive; and small ponies, or shelties, are bred wild on the heaths and pastures and exported in great numbers. About 4,000 of the inhabitants are employed in fishing.

Herring, cod, ling, and tusk are the principal kinds caught. The fishing season lasts about three months during summer. The only important manufactures are hosiery, straw plaiting, and the preparation of kelp; but the two latter have fallen off greatly of late years. The exports are fish, oil, cattle, horses, eggs, and woollen articles knit by hand. The value of exports is £100,000 a year. Places of worship are numerous, and nearly all the inhabitants can read and write. The people are small, active, and hardy. - Shetland is supposed to be the Thule of the ancients, and the first people known to have inhabited the islands were of Scandinavian origin. The present inhabitants are of their race. About 875 Harold Harfager reduced all the northern and western islands to his authority. Sigurd became earl of Orkney, Caithness, and Shetland; but the authority of the earls was little felt in the last, as they had no jurisdiction in civil affairs, and were merely military protectors or leaders. When James III. of Scotland married the princess Margaret of Denmark in 1469, he received as a pledge for the payment of her dowry the Orkney and Shetland islands, and they were never redeemed.

The Shetland islands with the Orkneys form a district which returns one member to parliament.