GUERNSEY, the second largest of the Channel islands, and the westernmost of the important members of the group, its chief town, St. Peter Port, on the east coast (in 2° 33' W., N.) being 3o m. from the nearest French coast to the east. The island, roughly triangular in form, is 94 m. long from N.E. to S.W. and has an extreme breadth of 5+ m. and an area of sq.m. Pop. (1931) with associated island 42,606.
The island is flat and low in the north, but rises gradually to a plateau (height above 30o ft.) in the south. The fracturing of the granitic rocks has resulted in steep-sided valleys and rectan gular bays, separated from one another by rocky headlands. The scenery of the south coast, with the bays of Moulin Huet, Saints and Petit Bot is noted. The west side of the island has a gradual slope and longer, wider valleys with a low, rocky coast and open bays (Rocquaine, Perelle, Vazon, Cobo, etc.) exposed to the Atlantic. On the sheltered eastern side are the two ports, St. Peter Port and St. Sampson, the harbour of St. Sampson being the remnant of an arm of the sea, which formerly isolated the Vale and L'Ancresse in the north-east from the rest of the island.
The soil is generally a light sandy loam, overlying an angular gravel which rests upon the weathered granite. Its fertility was formerly maintained by the use of "vraic" or sea-weed. This plant has its place in the folk-lore and traditional festivals of the island and the cutting of it, both for manure and fuel, is still regulated by law. The climate is mild and equable and the annual sunshine record is high, averaging 1,905 hours.
The typical form of settlement in Guernsey is that of separate farms, but there are old hamlets in the valleys and around some churches which were formerly related to open fields with com munal cultivation. The origin of settlement in the island is ob scure, but it is a region rich in megalithic monuments of Armori can type and most of the churches are definitely on sites of pre historic sanctity. Celtic saints have left their trace in legend and dedication ; there is also a Norse element in the population. About the nth century, most of the land was apportioned to Norman manors, but the usual organization became modified owing to absentee lords. Fishing supplemented cultivation, and in the 17th and i8th centuries, Guernsey developed maritime ad venture, including privateering for the English kings against the French during the frequent wars. The introduction of root crops (parsnips) and, with them, of a deep plough and associated agricultural co-operation, brought agricultural prosperity, but the end of privateering with the peace of 1815, meant a crisis for Guernsey in spite of its ships and shipyards and its utilization as a place for storage and maturation of southern wines. In the mid-19th century, a great local effort led to building of harbours preluding the development of rapid communications. Owing to its slope northward and its somewhat exposed position, Guernsey is just not warm enough in summer to grow grapes and tomatoes intensively in the open. It therefore specializes in cultivation under glass and large areas are covered with glass-houses. Nearly 34% of the population are gardeners. Guernsey has a separate herd of dairy cattle of great value. Some stone, which is quarried in the neighbourhood of St. Sampson, is shipped from that port, but the stone trade is on the decline.
For administrative purposes Guernsey is united with Alderney, Sark, Herm and the adjacent islets to form the bailiwick of Guernsey, separate from Jersey (see CHANNEL ISLANDS for con stitution). Guernsey is divided into ten parishes with St. Peter Port, its chief town, as one. The population of St. Peter Port in 1921 was 16,215. The population of the bailiwick of Guernsey nearly doubled between 1821 and 1901. There is good Romanesque work in the church of St. Michael, Vale, and the church of St. Peter Port is a notable building. Remains of monastic buildings are seen at Vale and on Lihou island, north of Rocquaine bay.